Effect of SGLT2 Inhibitor on Cardiomyopathy in a Rat Model of T2DM: Possible involvement of Cardiac Aquaporins

Diabetic cardiomyopathy (DCM) causes arrhythmia, heart failure, and sudden death. Empagliflozin, an SGLT-2 (Sodium glucose co-transporter) inhibitor, is an anti-diabetic medication that decreases blood glucose levels by stimulating urinary glucose excretion. Several aquaporins (AQPs) including AQP-1-3 and - 4 and their involvement in the pathogenesis in different cardiac diseases were detected. In the current study the effect of Empagliflozin on diabetic cardiomyopathy and the possible involvement of cardiac AQPs were investigated.

METHODS

56 adult male Sprague-Dawley rats were divided into 4 groups: Control, DCM: type 2 diabetic rats, low EMPA+DCM received empagliflozin (10 mg/kg/day) and high EMPA+DCM received empagliflozin (30 mg/kg/day) for 6 weeks.

RESULTS

Administration of both EMPA doses, especially in high dose group, led to significant improvement in ECG parameters. Also, a significant improvement in biochemical and cardiac oxidative stress markers (significant decrease in serum CK-MB, and malondialdehyde while increasing catalase) with decreased fibrosis and edema in histopathological examination and a significant attenuation in apoptosis (caspase-3) and edema (AQP-1& -4).

CONCLUSION

Both doses of Empagliflozin have a cardioprotective effect and reduced myocardial tissue edema with high dose having a greater effect. This might be due to attenuation of oxidative stress, fibrosis and edema mediated through AQP-1, - 3& - 4 expression.

3-Indolepropionic acid prevented chlorpyrifos-induced hepatorenal toxicities in rats by improving anti-inflammatory, antioxidant, and pro-apoptotic responses and abating DNA damage

The application of chlorpyrifos (CPF), an organophosphorus pesticide to control insects, is associated with oxidative stress and reduced quality of life in humans and animals. Indole-3-propionic acid (IPA) is a by-product of tryptophan metabolism with high antioxidant capacity and has the potential to curb CPF-mediated toxicities in the hepatorenal system of rats. It is against this background that we explored the subacute exposure of CPF and the effect of IPA in the liver and kidney of thirty rats using five cohort experimental designs (n = 6) consisting of control (corn oil 2 mL/kg body weight), CPF alone (5 mg/kg), IPA alone (50 mg/kg), CPF + IPA₁ (5 mg/kg + 25 mg/kg), and CPF + IPA₂ (5 mg/kg + 50 mg/kg). Subsequently, we evaluated biomarkers of hepatorenal damage, oxidative and nitrosative stress, inflammation, DNA damage, and apoptosis by spectrophotometric and enzyme-linked immunosorbent assay methods. Our results showed that co-treatment with IPA decreased CPF-upregulated serum hepatic transaminases, creatinine, and urea; reversed CPF downregulation of SOD, CAT, GPx, GST, GSH, Trx, TRx-R, and TSH; and abated CPF upregulation of XO, MPO, RONS, and LPO. Co-treatment with IPA decreased CPF-upregulated IL-1β and 8-OHdG levels, caspase-9 and caspase-3 activities, and increased IL-10. In addition, IPA averts CPF-induced histological changes in the liver and kidney of rats. Our results demonstrate that co-dosing CPF-exposed rats with IPA can significantly decrease CPF-induced oxidative stress, pro-inflammatory responses, DNA damage, and subsequent pro-apoptotic responses in rats' liver and kidneys. Therefore, supplementing tryptophan-derived endogenous IPA from exogenous sources may help avert toxicity occasioned by inadvertent exposure to harmful chemicals, including CPF-induced systemic perturbation of liver and kidney function.

Recent Progress in Environmental Toxins-Induced Cardiotoxicity and Protective Potential of Natural Products

Humans are unconsciously exposed to environmental toxins including heavy metals as well as various pesticides, which have deleterious effects on human health. Accumulating studies pointed out that exposure to environmental toxins was associated with various cardiopathologic effects. This review summarizes the main mechanisms of cardiotoxicity induced by environmental toxins (cadmium, arsenic and pesticides) and discusses the potential preventive effects of natural products. These findings will provide a theoretical basis and novel agents for the prevention and treatment of environmental toxins-induced cardiotoxicity. Furthermore, the limitations of current studies, future needs and priorities are discussed.

Modulation of Paraoxonase-1 and Apoptotic Gene Expression Involves in the Cardioprotective Role of Flaxseed Following Gestational Exposure to Diesel Exhaust Particles and/or Fenitrothion Insecticide

The developmental exposure to a single chemical may elicit apoptosis in the different fetal organs, while the combined effects are restricted. We have examined the protective role of flaxseed (FS) against diesel exhaust particles (DEPs)- and/or fenitrothion (FNT)-induced fetal cardiac oxidative stress and apoptosis. A total of 48 timed pregnant rats were divided into eight groups (n = 6). The first group was saved as the control and the second fed on 20% FS diet. Animals in the third, fourth, and fifth groups were administered with DEPs (2.0 mg/kg), FNT (3.76 mg/kg), and their combination, respectively, while the sixth, seventh, and eighth groups were supplemented with 20% FS through intoxication with DEPs, FNT, and their combination, respectively. Our results revealed that DEPs and/or FNT significantly elevated the level of protein carbonyl and superoxide dismutase activity in the fetal cardiac tissues. However, the catalase activity and total thiol level were decreased; besides the histopathological alterations were remarked. Moreover, DEPs and/or FNT exhibited significant down-regulation in the anti-apoptotic (Bcl-2) and paraoxonase-1 gene expression, and up-regulation in the apoptotic (Bax and caspase-3) gene expression along with DNA fragmentation. Remarkably, FS supplementation significantly ameliorated the fetal cardiac oxidative injury, down-regulated the expression of the apoptotic genes, up-regulated the anti-apoptotic and paraoxonase-1 gene expression, reduced DNA fragmentation, and alleviated the myocardial cell architectures. These findings revealed that FS attenuates DEPs- and/or FNT-induced apoptotic cell death by repairing the disturbance in the anti-apoptotic/pro-apoptotic gene balance toward cell survival in the fetal myocardial cells.

Propolis relieves the cardiotoxicity of chlorpyrifos in diabetic rats via alleviations of paraoxonase-1 and xanthine oxidase genes expression

Pesticides cardiotoxicity in case of diabetic-induced cardiac complications is unidentified. The probable amelioration role of propolis is gauged against the cardiotoxic effects of chlorpyrifos in the diabetic rats through paraoxonase-1 (PON1) and xanthine oxidase (XO) genes dysregulation. Fifty-six male rats were distributed (n = 7) into eight groups. The first one saved as control whereas the 2nd, 3rd, and 4th were kept for propolis aqueous extract (100 mg/kg), diabetes (60 mg/kg streptozotocin) and chlorpyrifos (2.5 mg/kg), respectively. The 5th was diabetes/chlorpyrifos combination, while 6th, 7th, and 8th were intubated with propolis for four weeks after diabetic induction, chlorpyrifos intoxication, and their combination, respectively. The plasma glucose, lipid profiles, cardiac enzymes and interleukin-6 (IL-6) significantly elevated, while insulin decreased in the diabetic and combination groups. Although the cardiac acetylcholinesterase, total thiols, and PON1 significantly reduced after diabetic and/or chlorpyrifos gavage, the protein carbonyl, superoxide dismutase, catalase, and XO significantly elevated. The mRNA genes expression of PON1 and XO have also confirmed the enzymatic activities. Interestingly, propolis significantly restored the hyperglycemia, hypoinsulinemia, hyperlipidemia, IL-6 elevations, and antioxidant defense system disorder. These records revealed that the immunomodulatory, anti-diabetic and antioxidant tasks are fine pointers for the cardiovascular defender of propolis especially during diabetes and/or pesticides exposure.