Original Article

Effects of Myrtus communis L. Extract and Apocynin on Lens Oxidative Damage and Boron Levels in Rats with a High Fat-Diet

10.4274/tjo.galenos.2021.27981

  • Rüya Kuru Yaşar
  • Dilruba Kuru
  • Ali Şen
  • Göksel Şener
  • Feriha Ercan
  • Ayşen Yarat

Received Date: 02.11.2020 Accepted Date: 28.10.2021 Turk J Ophthalmol 2021;51(6):344-350 PMID: 34963261

Objectives:

Nutritional obesity causes oxidant damage in the body and cataract formation in the lenses by increasing the formation of free radicals. Myrtus communis leaf extracts (Myr) have antioxidant properties, and apocynin (Apo) is an effective NADPH-oxidase inhibitor. The data on tissue boron levels are quite lacking. The aim of this novel study was to investigate the effects of Myr and Apo treatment on boron levels and oxidative lens damage in rats fed a high-fat diet (HFD).

Materials and Methods:

Wistar albino male rats were randomly divided into four groups: the control group, HFD group, HFD + Myr group, and HFD + Apo group. Body weight and blood lipids were determined before and after the experiment. After decapitating the rats, the lenses were removed and homogenized. Catalase (CAT) and superoxide dismutase (SOD) activities and boron, malondialdehyde (MDA), and reduced glutathione (GSH) levels in the lens homogenates were determined.

Results:

The HFD increased serum triglyceride (p<0.05), total cholesterol level (p<0.001), body weight (p<0.001), and lens MDA levels (p<0.01) and decreased lens GSH (p<0.05) and boron level (p<0.01), SOD (p<0.001), and CAT activity (p<0.001). However, Myr and Apo treatment reduced the rats’ body weight (p<0.001), serum triglyceride (p<0.05), and total cholesterol level (p<0.001) and increased lens boron (p<0.01; p<0.001), GSH levels (p<0.05; p<0.01), and CAT activity (p<0.001).

Conclusion:

Both Myr and Apo may be able to reduce oxidative stress in the lenses of obese rats caused by HFD by increasing boron levels.

Keywords: Obesity, lens, boron, antioxidants, Myrtus communis, apocynin

Introduction

Obesity is described as excessive or abnormal fat accumulation and is known to cause diabetes, hypertension, dyslipidemia, sleep apnea, respiratory problems, osteoarthritis, cardiovascular disease, and cancer. One of the mechanisms related to obesity and its associated comorbidities is the formation of excess oxidants and reactive oxygen species (ROS).1 Various studies have indicated that increased ROS formation in a high-fat diet (HFD) causes oxidant damage in the lens and cataract development.2,3

ROS are produced during normal cellular oxygen metabolism and are essential for numerous enzymatic reactions and biological functions. However, in some pathological conditions, they appear in excessive amounts and cause harmful effects at cellular level.4 Peroxidation of polyunsaturated fatty acids in biomembranes often occurs through exposure to ROS. Malondialdehyde (MDA) is generated by the peroxidation of fatty acids containing three or more double bonds. MDA, which is one of the major end products of lipid peroxidation, is frequently used in evaluating oxidant damage.5 Cells try to protect themselves from the harmful effects of ROS by developing various antioxidant systems. Endogenous antioxidants include catalase (CAT), superoxide dismutase (SOD), and glutathione (GSH). Dietary antioxidants contribute significantly to the endogenous antioxidant system in relieving oxidative stress.6

Plant phytochemicals have been shown to exhibit preventive activity against oxidative stress in various animal models.7,8 Myrtus communis, commonly known as myrtle, is among the edible foods and medicinal plants found in the Mediterranean and the Black Sea regions (including Turkey) and grows mainly in swamps and forests.9 M. communis leaf extracts (Myr) have been reported to have anti-inflammatory, antibacterial, and antioxidant properties.10,11 Nicotinamide adenosine dinucleotide phosphate (NADPH) oxidase is a multi-enzyme complex that catalyzes the one-electron reduction of molecular oxygen to the superoxide anion. Therefore, this reaction is the major source of ROS.12 Apocynin (Apo) which can be obtained from the root of the Apocynum cannabinum plant, is a potent NADPH oxidase inhibitor.13

The biological importance of boron is increasingly coming to light.14,15 Although boron is not yet considered an essential element for humans, it is classified as a possible essential element.16 The data on tissue boron levels, boron metabolism, and boron mechanism of action are quite lacking. There is no previous study in the literature that determines lens boron levels.

The aim of this study was to investigate the effects of Myr and Apo treatment on boron levels and oxidative lens damage in rats fed an HFD. To our knowledge, this study is the first to evaluate boron levels in the lens, and our results show that an HFD, Myr, and Apo can affect lens boron levels.


Materials and Methods


Animals and Conditions

The study was conducted in 2-month-old male Wistar albino rats (n=20) supplied by the Marmara University Application and Research Center for Experimental Animals. The rats were housed in an air-conditioned room with light-dark cycles of 12h:12h and constant relative humidity (65-70%) and temperature (22±2 oC). Ethical approval was obtained from the Marmara University Animal Care and Use Committee (30.03.2019).


Plant samples and preparation of Myrtus communis extract

The plant samples used in this study were collected from the city of Manisa (Turgutlu region) in 2010. The samples were identified by a botanist in the Marmara University, Faculty of Pharmacy. Voucher specimens were deposited in the Herbarium of Marmara University, Faculty of Pharmacy (MARE no: 13006). M. communis leaves (100 g) were dried in the shade at room temperature. The dried pulverized leaves were extracted with 96% EtOH using a Soxhlet apparatus. They were then evaporated in a vacuum at 40 oC until dry. This extract was stored in a dark container in the refrigerator (4 oC) until use.


Study Groups

After a 7-day acclimation period, the rats were weighed and randomly divided into four groups as follows:

• Control group (n=5): Rats were fed a standard rat diet for 16 weeks.

• HFD group (n=5): Rats were fed an HFD including 45% fat for 16 weeks.

• HFD + M. communis L. group (n=5): Rats were fed an HFD for 16 weeks and received Myr (100 mg/kg) via orogastric gavage during the last 4 weeks.

• HFD + Apo group (n=5): Rats were fed an HFD for 16 weeks and received Apo (Merck, Darmstadt, Germany) (25 mg/kg, in 15% dimethyl sulfoxide) via intraperitoneal injection during the last 4 weeks.


Biochemical Analysis

At the end of 16 weeks, the rats were weighed again and decapitated. Blood samples were collected for measurement of total cholesterol, high-density lipoprotein (HDL) cholesterol, and triglyceride levels and the lenses were removed and homogenized in 0.9% of NaCl solution to prepare 5% lens homogenates. The lens homogenates were stored at -80 oC until assaying. Boron, reduced GSH and MDA levels, SOD, and CAT activities in the lens homogenates were determined using the modified carminic acid17, Beutler 18, Ledwozwy et al.19, Mylorie et al.20, and Aebi21 methods, respectively.


Statistics Analysis

Statistical analysis was done using GraphPad Prism 5.0 (GraphPad Software, San Diego, USA). All data were expressed as mean ± standard error. Analysis of variance (ANOVA) was used for multiple comparisons followed by Tukey’s post-hoc test. A p-value less than 0.05 was considered significant.


Results

This study used an HFD-induced obesity model. Weight values at the beginning and end of the experiment are shown in Figure 1. At the end of week 16, rats in the HFD group were significantly heavier than those in the control group (p<0.001), whereas treatment with Myr and Apo significantly reduced this increase in weight.

The total cholesterol, triglyceride, and HDL-cholesterol of rats at week 16 are shown in Figure 2. Rats in the HFD group had higher triglyceride (p<0.05) (Figure 2a) and total cholesterol levels (p<0.001) (Figure 2b) and lower HDL-cholesterol levels (p<0.001) (Figure 2c) than the control group. Rats that received Myr and Apo also had significantly lower total cholesterol and triglyceride levels and significantly higher HDL-cholesterol levels than those in the HFD group.

At the end of 16 weeks, lens MDA levels were significantly higher in the HFD group than in the control group (p<0.01) (Figure 3a). Lens MDA levels of Apo-treated rats were significantly lower than those of the control group (p<0.05) and the HFD group (p<0.001). Moreover, the lens MDA levels of the Apo-treated group were significantly lower than those of the Myr-treated group (p<0.001). Lens GSH levels in the HFD group were significantly lower than those of the control group (p<0.05) (Figure 3b). Lens GSH levels were significantly higher in the Apo-treated (p<0.01) and Myr-treated (p<0.05) groups than in the HFD group. Lens CAT (Figure 3c) and SOD (Figure 3d) activities were significantly lower in the HFD group than in the control group (p<0.001). There was no significant difference in SOD activity between the Apo-treated and HFD groups. However, the Myr-treated group had higher SOD activity than the HFD group (p<0.05). Lens CAT activity in the Myr- and Apo-treated groups was significantly higher than in the control and HFD groups (p<0.001).

Lens boron levels in the HFD, Myr-treated, and Apo-treated groups were significantly lower than those of the control group (p<0.001). Moreover, lens boron levels in the Myr-treated (p<0.05) and Apo-treated (p<0.001) groups were higher than those of the HFD group (Figure 4).


Discussion

It is known that HFD is strongly associated with obesity. HFDs have been used for decades to induce dyslipidemia and obesity in rodents.22 In the present study, body weight was significantly higher in HFD-fed rats (45% fat) compared to the control group (standard rat diet). However, this increase in body weight was less pronounced in the Myr- and Apo-treated groups. Similar to our study, it has been shown that Myr treatment (200 and 400 mg/kg) in rats23 and Apo treatment (5 mM, dissolved in drinking water) in mice reduced weight gain in animals receiving an HFD.24 It has been shown that polyphenols and flavonoids regulate the activity of PPAR-g (peroxisome proliferator-activated receptor), the inhibition of angiogenesis in adipose tissue, and the SREBP (sterol regulatory-element binding proteins) pathway.25,26 Myr is rich in polyphenols and flavonoids. Therefore, it is thought that it can reduce body weight. It has been suggested that Apo can achieve this by preventing insulin resistance.27

In recent years, the use of plant extracts and plant-derived compounds has been increasing in research studies for the prevention and treatment of many cardiovascular diseases.28 Rosa et al.29 reported that the semi-myrtucommulone and myrtucommulone-A compounds in Myr has antiatherogenic effects. Meng et al.27 showed that Apo significantly improved dyslipidemia in mice with HFD-induced obesity. In the present study, the total cholesterol and triglycerides levels of rats fed an HFD were significantly higher than those of the control group, while their levels of HDL cholesterol were lower. However, triglyceride and total cholesterol levels were significantly lower in the Myr and Apo treatment groups than in the HFD group, while HDL cholesterol was higher.

Oxidative damage is an important factor that causes cataracts, which are responsible for almost half of all cases of human blindness worldwide. Generally, oxidation is considered to be a key feature of cataract formation.30 HFD may contribute to cataract formation by increasing ROS in the lens.2,3 A case-control study evaluating the relationship between diet and cataract risk showed that the risk of cataract increased with total dietary fat intake (p<0.001).31

Ocular tissues contain many antioxidants such as enzymes, proteins, ascorbic acid, glutathione, cysteine, and tyrosine to protect against excess ROS. The lens is a tissue that is particularly vulnerable to oxidative damage.32 It is also known that in cataract patients, the level of hydrogen peroxide (H2O2) in the lens may triple compared to a healthy lens.33 It has been shown that SOD protects the lens from oxidative damage from H2O2 in rats.34 It is known that GSH in the lens contributes to the preservation of lens transparency.35 GSH protects thiol groups in lens proteins against ROS. This is very important for the normal function of the lens epithelium Na/K-ATPase enzyme, which affects cell permeability.35 It is known that NADPH oxidase is the main source of ROS and Apo is an effective NADPH oxidase inhibitor.36 As the major end product of lipid peroxidation, MDA is considered a toxic compound in the eye due to its high cross-linking ability with the lipid membrane.37 In the present study, tissue oxidative damage was monitored with lens MDA levels. In rats fed an HFD, lens MDA levels were significantly higher than those of the control group. This result shows that HFD increases oxidative damage. Moreover, lens MDA levels in the Apo treatment group were significantly lower than in the control and HFD groups. Furthermore, lens GSH and CAT activity in the Apo treatment group were significantly higher than in the HFD group. These results show that Apo can protect the lens from oxidative damage. In another study, treatment with 2.4 g/L Apo (in drinking water) for 5 weeks in mice fed an HFD reduced systemic and hepatic oxidative stress.27 It was also reported that cataract progression was reduced in rabbits given 20 mg/kg/day Apo intraperitoneally.38

Various studies have shown that M. communis has antimicrobial, anti-inflammatory, and antioxidant effects.39,40,41 In the literature, studies showing the effect of M. communis on lens antioxidant status are limited. In streptozotocin-induced diabetic rats, M. communis extract was shown to increase lens GSH (p<0.05) and MDA levels (p<0.05).42 In the present study, lens MDA levels did not differ significantly between the HFD and Myr-treated groups. However, GSH levels, CAT and SOD activities were significantly higher in the Myr-treated group than in the HFD group.

Boron is present in human tissues and body fluids as a natural result of boron intake from food and drinking water.14 Studies on the distribution of boron in tissues are limited in the literature.15 Data on the mechanism of action of boron is insufficient. It is reported that boron may react with cis-hydroxyl group-containing biomolecules such as polysaccharides, adenosine-5-phosphate, pyridoxine, flavins (e.g., flavin adenine dinucleotide), dehydroascorbic acid, and pyridine (e.g., NAD+ or NADP).14 Having low atomic weight and being able to make compounds with organic molecules are thought to be important for the biological function of boron. It is also thought that boron may be effective in hormone receptors and trans-membrane signals, cell membrane functions, and stability.43

Boron compounds ingested orally are rapidly converted to boric acid in the gastrointestinal tract and are nearly completely absorbed and distributed to the tissues through the blood.14 Studies have shown that 84-85% of dietary boron is excreted in urine. Although it is known that the distribution of boron into tissues involves passive diffusion and/or sodium-dependent borate carrier-1 (NaBC1), it has not been fully elucidated yet.44 Studies are needed to determine how boron is transported to the lens. In rats, the “no observed adverse effect level” (NOAEL) for developmental effects of boron is 9.6 mg boron/kg body weight/day. The oral lethal dose (LD50) for boron in rats is 400-700 mg/kg.45,46 The available human exposure studies are very limited due to geographical conditions and dietary differences, and the toxic oral reference dose and recommended dietary allowance (RDA) of boron for humans have not been clearly established. However, it is known that it is not possible to exceed the safe intake level (20 mg/day) and toxic dose (500 mg/day) through dietary and water intake.47

There is no previous study in the literature that examines lens boron levels. Therefore, we could not compare these results. However, it has been shown that the boron level decreases in plasma, kidney, brain, and liver tissue of rats receiving malathion, which induces oxidative stress. Boron levels in these tissues were found to be considerably lower than our lens boron levels.48 Similar to the above study, lens boron levels also decreased with an HFD in the present study. Various studies have shown that boron plays a role in energy and lipid metabolism. It increases thermogenesis by causing the expression of uncoupling proteins in adipose tissue49 and inhibits transcription activity of SREBP.50 In rats fed an HFD, it has been shown that increased boron intake reduces body weight by altering serum L-carnitine and insulin-like growth factor 1 levels.51 In humans, it has been reported that high dietary boron intake increases serum and saliva boron levels and reduces body weight, serum low-density lipoprotein cholesterol, very-low-density lipoprotein cholesterol, total cholesterol, and triglyceride levels.44


Study Limitations

A limitation of the present study was that we did not determine boron intake by food and water. Drinking water from the same source was given to all groups. Therefore, boron intake by water can be assumed to be similar for all groups. However, the boron intake of the HFD group may have been lower than that of the treated HFD groups. The reason for the increased boron levels may arise from both the antioxidant properties of Myr and Apo, as well as from boron intake with Myr. Increased boron levels may enhance the effects of Myr and Apo. The increase in lens boron level in HFD + Apo group rats suggests that boron may be important in preventing lens oxidative damage. Boron can be a mediator in the prevention of lens oxidative damage. Further studies evaluating the effects of boron supplements on HFDs and lens boron levels are needed.


Conclusion

Both Apo and Myr may be able to reduce oxidative stress in the lenses of HFD-induced obese rats by increasing boron levels. More detailed studies are needed to elucidate boron’s distribution and mechanism of action in the lens and whether it has any effect on cataract formation. Boron levels may be a novel indicator of reduced oxidative stress.


Acknowledgments: The authors would like to thank Dr. Gizem Emre for her help in identification of the plant material.

Ethics

Ethics Committee Approval: Ethical approval was obtained from the Marmara University Animal Care and Use Committee (30.03.2019).

Informed Consent: Informed consent is not necessary because our study is an experimental study.

Peer-review: Externally peer reviewed.

Authorship Contributions

Surgical and Medical Practices: G.Ş., F.E., Concept: G.Ş., F.E., A.Y., Design: G.Ş., F.E., A.Y., Data Collection or Processing: A.Ş., G.Ş., F.E., A.Y., Analysis or Interpretation: R.K.Y., D.K., A.Ş., G.Ş., F.E., A.Y., Literature Search: R.K.Y., D.K., A.Y., Writing: R.K.Y., D.K., A.Y.

Conflict of Interest: No conflict of interest was declared by the authors.

Financial Disclosure: The authors declared that this study received no financial support.

Images

  1. Matsuda M, Shimomura I. Increased oxidative stress in obesity: implications for metabolic syndrome, diabetes, hypertension, dyslipidemia, atherosclerosis, and cancer. Obes Res Clin Pract. 2013;7:e330-e341.
  2. Nakazawa Y, Ishimori N, Oguchi J, Nagai N, Kimura M, Funakoshi-Tago M, Tamura M. Coffee brew intake can prevent the reduction of lens glutathione and ascorbic acid levels in HFD-fed animals. Exp Ther Med. 2019;17:1420-1425.
  3. Umapathy A, Donaldson P, Lim J. Antioxidant delivery pathways in the anterior eye. Biomed Res Int. 2013;2013:207250.
  4. Zhang J, Wang X, Vikash V, Ye Q, Wu D, Liu Y, Dong W. Ros and ROS-mediated cellular signaling. Oxid Med Cell Longev. 2016;2016:4350965.
  5. Ayala A, Muñoz MF, Argüelles S. Lipid peroxidation: production, metabolism, and signaling mechanisms of malondialdehyde and 4-hydroxy-2-nonenal. Oxid Med Cell Longev. 2014;2014:360438.
  6. Yadav A, Kumari R, Yadav A, Mishra JP, Srivatva S, Prabha S. Antioxidants and its functions in human body-a review. Res Environ Life Sci. 2016;9:1328-1331.
  7. Zhang YJ, Gan RY, Li S, Zhou Y, Li AN, Xu DP, Li HB. Antioxidant phytochemicals for the prevention and treatment of chronic diseases. Molecules. 2015;20;21138-21156.
  8. Lee MT, Lin WC, Yu B, Lee TT. Antioxidant capacity of phytochemicals and their potential effects on oxidative status in animals-a review. Asian-Australas J Anim Sci. 2017;30:299-308.
  9. Karademir FK, Avunduk S. Antibacterial and antioxidant activity of Myrtus Communis L. growing wild in Marmaris. Gida. 2015;40:193-199.
  10. Sen A, Yuksel M, Bulut G, Bitiş L, Ercan F, Ozyılmaz-Yay N, Akbulut O, Cobanoglu H, Ozkan S, Sener G. Therapeutic potential of Myrtus Communis subsp. communis extract against acetic acid-induced colonic inflammation in rats. J Food Biochem. 2017;41:e12297.
  11. Hennia A, Miguel MG, Nemmiche S. Antioxidant activity of Myrtus Communis l. and Myrtus Nivellei batt. & trab. extracts: a brief review. Medicines. 2018;5:89.
  12. Petrônio MS, Zeraik ML, Fonseca LM, Ximenes VF. Apocynin: chemical and biophysical properties of a NADPH oxidase inhibitor. Molecules. 2013;18:2821-2839.
  13. Di PR, Mazzon E, Paterniti I, Impellizzeri D, Bramanti P, Cuzzocrea S. Apocynin, a plant-derived drug, might be useful in the treatment of myocardial ischemia reperfusion injury in rat hearts. Eur J Inflamm. 2011;9:157-168.
  14. Kuru R, Yarat A. Boron and a current overview of its effects on health. Clin Exp Health Sci. 2017;7:107-114. (in Turkish).
  15. Kuru R, Mutlu EK, Cempel E, Celik SB, Yarat A. Evaluation of dietary boron in terms of health: a retrospective study. Clin Exp Health Sci. 2018;8:296-300.
  16. Baldivia SA, Ibarra RG, Torre RR, Sobrino GG, Tasistro A, Etchevers-Barra JD, Reyna-Santamaría L. Five causes why boron essentiality on humans has not been confirmed: a hypothesis. Integr Food Nutr Metab. 2016;4:1-5.
  17. Kuru R, Yilmaz S, Tasli PN, Yarat A, Sahin F. Boron content of some foods consumed in Istanbul, Turkey. Biol Trace Elem Res. 2019;187:1-8.
  18. Beutler E. Reduced glutathione (GSH). In: Bergmeyen HV, ed. Red Blood Cell Metabolism: a Manual of Biochemical Methods. 2nd ed. New York: Grune and Stratton; 1975:112-114.
  19. Ledwozwy A, Michalak J, Stepien A, Kadziolka A. The relationship plasma triglycerides, cholesterol, total lipids, and lipid peroxidation products during human atherosclerosis. Clin Chim Acta. 1986;155:275-284.
  20. Mylorie AA, Collins H, Umbles C, Kyle J. Erythrocyte superoxide dismutase activity and other parameters of cupper status in rats ingesting lead acetate. Toxicol Appl Pharmacol. 1986;82:512-520.
  21. Aebi H. Catalase. In: Bergmeyer HU, ed. Methods of Enzymatic Analysis. New York: Academic Press; 1974:673-680.
  22. Xu JZ, Fan JG, Ding XD, Qiao L, Wang GL. Characterization of high fat, diet induced, non-alcoholic steatohepatitis with fibrosis in rats. Dig Dis Sci. 2010;55:931-940.
  23. Ahmet AL. Flavonoid content and antiobesity activity of leaves of Myrtus Communis. Asian J Chem. 2013;25:6818-6822.
  24. Du J, Li J. BAS/BSCR23 Apocynin treatment reduces high-fat diet-induced obesity and hypertension but has no significant effect on hyperglycemia. Heart. 2010;96:e19.
  25. El-Moselhy MA, Taye A, Sharkawi SS, El-Sisi SF, Ahmed AF. The antihyperglycemic effect of curcumin in high fat diet fed rats. Role of TNF-alpha and free fatty acids. Food Chem Toxicol. 2011;49:1129-1140.
  26. Li Y, Jiang Z, Xue D, Den G, Li M, Liu X, Wang Y. Mycoplasma ovipneumoniae induces sheep airway epithelial cell apoptosis through an ERK signalling-mediated mitochondria pathway. BMC Microbiol. 2016;16:222.
  27. Meng R, Zhu DL, Bi Y, Yang DH, Wang YP. Anti-oxidative effect of apocynin on insulin resistance in high-fat diet mice. Ann Clin Lab Sci. 2011;41:236-243.
  28. Rastogi S, Pandey MM, Rawat AK. Traditional herbs: a remedy for cardiovascular disorders. Phytomedicine. 2016;23:1082-1089.
  29. Rosa A, Melis MP, Deiana M, Atzeri A, Appendino G, Corona G, Incani A, Loru D, Dessi MA. Protective effect of the oligomeric acylphloroglucinols from Myrtus Communis on cholesterol and human low density lipoprotein oxidation. Chem Physics Lipids. 2008;155:16-23.
  30. Kisic BM, Dijana M, Zoric L, Ilić A, Dragojevic I. Antioxidant capacity of lenses with age-related cataract. Oxid Med Cell Longev. 2012;2012:467130.
  31. Theodoropoulou S, Samoli E, Theodossiadis PG, Papathanassiou M, Lagiou A, Lagiou P, Tzonoyu. Diet and cataract: a case-control study. Int Ophthalmol. 2014;34:59-68.
  32. Cabrera MP, Chihuailaf RH. Antioxidants and the integrity of ocular tissues. Vet Med Int. 2011;2011:905153.
  33. Ho MC, Peng JY, Chen SJ, Chiou SH. Senile cataracts and oxidative stress. J Gerontol Geriatr. 2010;1:17-21.
  34. Lin D, Barnett M, Grauer L, Robben J, Jewell A, Takemoto L, Takemoto DJ. Expression of superoxide dismutase in whole lens prevents cataract formation. Mol Vis. 2005;11:853-858.
  35. Giblin FJ. Glutathione: a vital lens antioxidant. J Ocul Pharmacol Ther. 2000;16:121-135.
  36. Sener TE, Yuksel M, Ozyılmaz-Yay N, Ercan F, Akbal C, Simsek F, Sener G. Apocynin attenuates testicular ischemia-reperfusion injury in rats. J Pediatr Surg. 2015;50:1382-1387.
  37. Cao J, Wang T, Wang M. Investigation of the anti-cataractogenic mechanisms of curcumin through in vivo and in vitro studies. BMC Ophthalmol. 2018;18:48.
  38. Polat N, Ozer MA, Parlakpinar H, Vardi N, Gunduz A, Colak C. Investigation of the effect of apocynin on experimental traumatic cataract model. Turkiye Klinikleri J Ophthalmol. 2017;26:253-257.
  39. Ozbeyli D, Sen A, Kaya OTC, Ertas B, Aydemir S, Ozkan N, Yuksel M, Sener G. Myrtus communis leaf extract protects against cerulein-induced acute pancreatitis in rats. J. Food Biochem. 2020;44:e13130.
  40. Ozcan O, Ipekci H, Alev B, Ustundag UV, Ak E, Sen A, Alturfan EE, Sener G, Yarat A, Cetinel S, Akbay TT. Protective effect of Myrtle (Myrtus Communis) on burn induced skin injury. Burns. 2019;45:1856-1863.
  41. Sen A, Ozkan S, Recebova K, Cevik O, Ercan F, Kervancıoglu DE, Bitis L, Sener G. Effects of Myrtus Communis extract treatment in bile duct ligated rats. J Surg Res. 2016;205:359-367.
  42. Ozkol H, Tuluce Y, Dilsiz N, Koyuncu I. Therapeutic potential of some plant extracts used in Turkish traditional medicine on streptozocin-induced type 1 diabetes mellitus in rats. J Membr Biol. 2013;246:47-55.
  43. Nielsen FH, Meacham SL. Growing evidence for human health benefits of boron. J Evid Based Complementary Altern Med. 2011;16:169-180.
  44. Kuru R, Yilmaz S, Balan G, Tuzuner BA, Tasli PN, Akyuz S, Ozturk FY, Altuntas Y, Yarat A, Sahin F. Boron-rich diet may regulate blood lipid profile and prevent obesity: A non-drug and self-controlled clinical trial. J Trace Elem Med Biol. 2019;54:191-198.
  45. Bolt HM, Basaran N, Duydu Y. Effects of boron compounds on human reproduction. Arch Toxicol. 2020;94:717-724.
  46. Weir RJ, Fisher RS. Toxicologic studies on borax and boric acid. Toxicol Appl Pharmacol. 1972;23:351-364.
  47. Kuru R, Yilmaz S, Sacan O, Yanardag R, Yarat A, Sahin F. Boron concentrations in tap water in many cities of Turkey. Toxicol Environ Chem. 2020;102:240-249.
  48. Coban FK, Ince S, Kucukkurt I, Demirel HH, Hazman O. Boron attenuates malathion-induced oxidative stress and acetylcholinesterase inhibition in rats. Drug Chem Toxicol. 2015;38:391-399.
  49. Aysan E, Şahin F, Telci D, Erdem M, Müslumanoglu M, Yardımcı E, Bektaşoğlu H. Mechanism of body weight reducing effect of oral boric acid intake. Int J Endocrinol. 2013;2013:1-5.
  50. Doğan A, Demirci S, Abdik H, Bayrak OF, Güllüoğlu S, Tüysüz EC, Gusev O, Rizvanov AA, Nikerel E, Şahin F. A new hope for obesity management: Boron inhibits adipogenesis in progenitor cells through the Wnt/b-catenin pathway. Metabolism. 2017;69:130-142.
  51. Atakisi O, Dalginli KY, Gulmez C, Kaya R, Ozden O, Kart A, Atakisi E. Boric acid and borax supplementation reduces weight gain in overweight rats and alter L-Carnitine and IGF-I Levels. Int J Vitam Nutr Res. 2020;90:221-227.