Voluntary exercise prevents lead-induced elevation of oxidative stress and inflammation markers in male rat blood

Heavy Metal Exposure: Molecular Pathways, Clinical Implications, and Protective Strategies

Heavy metals are often found in soil and can contaminate drinking water, posing a serious threat to human health. Molecular pathways and curation therapies for mitigating heavy metal toxicity have been studied for a long time. Recent studies on oxidative stress and aging have shown that the molecular foundation of cellular damage caused by heavy metals, namely, apoptosis, endoplasmic reticulum stress, and mitochondrial stress, share the same pathways as those involved in cellular senescence and aging. In recent aging studies, many types of heavy metal exposures have been used in both cellular and animal aging models. Chelation therapy is a traditional treatment for heavy metal toxicity. However, recently, various antioxidants have been found to be effective in treating heavy metal-induced damage, shifting the research focus to investigating the interplay between antioxidants and heavy metals. In this review, we introduce the molecular basis of heavy metal-induced cellular damage and its relationship with aging, summarize its clinical implications, and discuss antioxidants and other agents with protective effects against heavy metal damage.

Endoplasmic reticulum stress associated with lead (Pb)-induced olfactory epithelium toxicity in an olfactory dark basal cell line

Lead (Pb) can damage organs and also have undesirable effects on neural development. To explore the effects of Pb on olfactory cells, we investigated Pb-induced cell toxicity in the DBC1.2 olfactory cell line, with a focus on endoplasmic reticulum (ER) stress, apoptosis, and necroptosis. Representative markers of ER stress, apoptosis, and necroptosis were analyzed by quantitative PCR. The mRNA expression levels of GRP94, GRP78, spliced XBP1, PERK, and ATF6 increased significantly after Pb exposure in a dose-dependent manner. The expression of Caspase 3 and Caspase 12 did not increase after Pb exposure, which suggested that apoptosis-induced cell death was not activated after Pb exposure. However, the mRNA of RIPK3 and MLKL showed increases in expression, which indicated that necroptosis-induced cell death was activated after Pb exposure. These results indicate that Pb exposure induced dose-dependent cytotoxicity through ER stress and necroptosis pathways in DBC1.2 cells, whereas the apoptosis pathway was not significantly stimulated. HEPES buffer showed a partial protective effect in terms of ER stress, apoptosis, and necroptosis. In summary, the necroptosis pathway plays a crucial rule in Pb exposure-induced cytotoxicity in olfactory cells.

Combination Effect of Voluntary Exercise and Garlic (Allium sativum) on Oxidative Stress Biomarkers and Lipid Profile in Healthy Rats

Background: We evaluated the combination effect of voluntary exercise and garlic on serum oxidative stress biomarkers and lipid profile in healthy rats. Methods: The rats were randomly assigned to four groups (n=7): Control, Garlic, Exercise, and Garlic + Exercise. Rats were fed with raw fresh garlic homogenate by oral gavage (250 mg/kg) or were subjected to voluntary exercise using stainless steel running wheels alone or together for 6 weeks. The samples were collected at the end of the experiment. Results: After 6 weeks, total cholesterol, low-density lipoprotein (LDL), triglycerides (TG) and high-density lipoprotein (HDL) levels improved in both garlic and exercise group, compared with the control group. We also found that serum glutathione peroxidase (Gpx), Superoxide dismutase (SOD), Catalase (CAT), and Total antioxidant (TAC) levels enhanced significantly following the above-mentioned interventions. Furthermore, simultaneous treatment of rats with garlic and voluntary exercise had an additive effect on these parameters. However, malondialdehyde (MDA) level was not significantly different from control group during our protocol. Conclusion: The findings revealed that simultaneous treatment of rats with garlic and voluntary exercise improved antioxidant defense system and lipid profile in an additive manner in healthy rats.

Combination effect of voluntary exercise and garlic (Allium sativum) on oxidative stress, cholesterol level and histopathology of heart tissue in type 1 diabetic rats

Introduction: This study aimed to evaluate the combination effect of voluntary exercise and garlic on oxidative markers, cholesterol level and histological alterations in streptozotocin (STZ)- induced diabetes in rat heart.

Methods: Thirty-five male Wistar rats were randomly assigned into five experimental groups (n=7): Control, Diabetes, Diabetes+Garlic, Diabetes+Exercise, Diabetes+Garlic+Exercise groups. Diabetes was induced by STZ (ip, 50 mg/kg) in animals. Animals received garlic homogenate (250 mg/kg) by oral gavage or subjected to voluntary exercise alone or together for 6 weeks. At the end of intervention blood and heart tissue samples were obtained and used for measurement of glycosylated haemoglobin (HbA1c), cholesterol, total antioxidant capacity (TAC), malondialdehyde (MDA) levels and histological analysis.

Results: Improved blood glucose, cholesterol, total antioxidant capacity, and MDA levels were established in both Diabetes+Garlic and Diabetes+Exercise groups. Additionally, staining with Hematoxylin and Eosin (H&E) revealed that voluntary exercise and garlic alone and together reduced interstitial edema, leukocyte infiltration, and myonecrosis. Furthermore, simultaneous treatment of diabetic rats with garlic and exercise training had an additive effect on these parameters.

Conclusion: The findings indicated that combination therapy with garlic and voluntary exercise may present more beneficial effects in heart histological remodeling in diabetic rats than the use of garlic or voluntary exercise alone and that these beneficial effects might be associated with enhancement in cholesterol, total antioxidant capacity, and MDA levels.

Folic acid protects against lead acetate-induced hepatotoxicity by decreasing NF-κB, IL-1β production and lipid peroxidation mediataed cell injury

Folic acid plays an important role in cellular metabolic activities. The present study was designed to investigate the protective effect of folic acid against lead acetate-induced hepatotoxicity. Twenty four male Wistar albino rats were randomly divided into four groups, six animals each. Negative control group received the vehicle, positive control group received 1mg/kg folic acid for five consecutive days/week for 4 weeks orally, lead-exposed group received 10mg/kg lead acetate intraperitoneally (IP) for five consecutive days/week for 4 weeks, and lead-treated group received 10mg/kg lead acetate IP and 1mg/kg folic acid orally for five consecutive days/week for 4 weeks concurrently. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and γ- glutamyltransferase (GGT) were measured. Hepatic total peroxide and interleukin-1β (IL-1β) were also investigated. Histopathological studies using hematoxylin-eosin (H&E) and periodic acid shiff's (PAS) were carried out. The expression of nuclear factor kappa B (NF-κB) was evaluated using immunohistochemistry. Serum AST, ALT and GGT and hepatic total peroxide and IL-1β were significantly increased in lead-exposed group and were positively correlated with hepatic lead level. Moreover, lead-exposed rats showed hydropic degeneration, nuclear vesiculation, high lymphocytic infiltration, depletion of glycogen content and NF-κB expression. Concomitant folic acid administration resulted in a significant alleviation of biochemical and structural alteration-induced by lead. This was associated with reduction of hepatic total peroxide and IL-1β and reduction of NF-κB expression. In conclusion, folic acid protects against lead acetate-induced hepatotoxicity by decreasing NF-κB, IL-1β production and lipid peroxidation mediataed cell injury.