Expression Changes of Apoptotic Genes in Tissues from Mice Exposed to Nicotine

Dexpanthenol protects against nicotine-induced kidney injury by reducing oxidative stress and apoptosis through activation of the AKT/Nrf2/HO-1 pathway

Dexpanthenol (DEX), a subtype of vitamin B5, plays an important role in anabolic reactions, cellular energy and regeneration in the body. Nicotine has been shown to induce kidney damage through the mechanisms of oxidative stress and apoptosis. The purpose of this study was to investigate the potential protective effects of DEX against nicotine-induced kidney damage through modulation of the AKT/Nrf2/HO-1 signaling pathway. Male rats were intraperitoneally administered with 0.5 mg/kg/day nicotine and/or 500 mg/kg/day DEX for 8 weeks. Following administration, renal function tests were conducted on serum samples, and histopathological examinations and analysis of oxidative stress markers and antioxidant enzymes were performed on tissue samples. Protein levels of Akt, Nrf-2, HO-1, Bcl-xL, and Caspase-9 were also evaluated. Nicotine administration resulted in decreased protein levels of p-Akt, Nrf-2, HO-1, and Bcl-xL and increased Caspase-9 protein levels. In addition, nicotine administration caused an increase in MDA, TOS, and OSI levels and a decrease in GSH, GSH-Px, GST, CAT, SOD, and TAS levels. Additionally, BUN and Creatinine levels increased after nicotine administration. DEX administration positively regulated these parameters and brought them closer to control levels. Nicotine-induced kidney injury caused apoptosis and oxidative stress through Caspase-9 activation. DEX effectively prevented nicotine-induced kidney damage by increasing intracellular antioxidant levels and regulating apoptosis through Bcl-xL activation. These findings suggest that DEX has potential as a protective agent against nicotine-induced kidney damage.

Alpha7 Nicotinic Acetylcholine Receptor Mediates Nicotine-induced Apoptosis and Cell Cycle Arrest of Hepatocellular Carcinoma HepG2 Cells

Purpose: The cytotoxic properties upon treatment with nicotine have been reported in several studies, but the underlying mechanisms remain not fully defined. The alpha7 nicotinic acetylcholine receptor (α7nAChR) is one of the important nicotinic receptors, which nicotine partly by binding to this receptor exerts its effects. The current study aimed to investigates the influences of nicotine on cellular proliferative and apoptotic activities and tried to determine the involvement of α7nAChR in these functions. Methods: Human hepatocellular carcinoma (HepG2) cell line was used to determine the individual or combined effects of treatments with nicotine (10 μM) and specific siRNA (100 nM) targeting α7nAChR expression. The MTT assay, DAPI staining assay, and flow cytometry assay were applied to measure the cell viability, apoptosis and cell cycle progression of the cells, respectively. In addition, the changes in the mRNA level of the genes were assessed by qRT-PCR. Results: Compared to control groups, the cells treated with nicotine exhibited significant dosedependent decreases in cell viability (log IC50 = -5.12±0.15). Furthermore, nicotine induced apoptosis and cell cycle arrest especially at G2/M Phase. The qRT-PCR revealed that nicotine increased the mRNA levels of α7nAChR as well as caspase-3 and suppressed the expression of cyclin B1. Treatment with α7-siRNA abolished these effects of nicotine. Conclusion: These experiments determined that upregulation of α7nAChR by nicotine inhibits HepG2 cells proliferation and induces their apoptosis. These effects blocked by treatment with α7-siRNA, which indicates the involvement of α7nAChR pathways in these processes.

Effect of Harmine on Nicotine-Induced Kidney Dysfunction in Male Mice

Background:

The nicotine content of cigarettes plays a key role in the pathogenesis of kidney disease. Harmine is a harmal-derived alkaloid with antioxidant properties. This study was designed to evaluate the effects of harmine against nicotine-induced damage to the kidneys of mice.

Methods:

In this study, 64 male mice were randomly assigned to eight groups: saline and nicotine-treated groups (2.5 mg/kg), harmine groups (5, 10, and 15 mg/kg), and nicotine (2.5 mg/kg) + harmine-treated groups (5, 10, and 15 mg/kg). Treatments were administered intraperitoneally daily for 28 days. The weights of the mice and their kidneys, kidney index, glomeruli characteristics, thiobarbituric acid reactive species, antioxidant capacity, kidney function indicators, and serum nitrite oxide levels were investigated.

Results:

Nicotine administration significantly improved kidney malondialdehyde (MDA) level, blood urea nitrogen (BUN), creatinine, and nitrite oxide levels and decreased glomeruli number and tissue ferric reducing/antioxidant power (FRAP) level compared to the saline group (P < 0.05). The harmine and harmine + nicotine treatments at all doses significantly reduced BUN, kidney MDA level, creatinine, glomerular diameter, and nitrite oxide levels and increased the glomeruli number and tissue FRAP level compared to the nicotine group (P < 0.05).

Conclusions:

It seems that harmine administration improved kidney injury induced by nicotine in mice.

The Effects of Thymoquinone Against Morphine-induced Damages on Male Mice Liver

BACKGROUND

Morphine is a pain medication. It is mostly processed in liver and reasons disturbing effects. It can increase the production of free radicals. Thymoquinone is a phytochemical compound found in the plant Nigella sativa. It has diverse pharmacological properties such as antioxidant and anticancer. This study was intended to assess the effects of thymoquinone against morphine damages on the liver of mice.

METHODS

In this study, various doses of thymoquinone (4.5, 9, and 18 mg/kg) and thymoquinone plus morphine was administered (once a day) intraperitoneally to 48 male mice for 20 consequent days. These mice were randomly assigned to eight groups (n = 6). Aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, serum nitric oxide (NO) levels, liver weight, and histology have been studied.

RESULTS

The results indicated that morphine administration significantly increased the mean diameter of central hepatic vein and hepatocyte, blood serum NO level, liver enzymes level, and decreased liver weight compared to saline group (P < 0.05). However, thymoquinone and thymoquinone plus morphine administration significantly enhanced liver weight and reduced the mean diameter of hepatocyte, central hepatic vein, liver enzymes, and NO levels in all groups compared to morphine group (P < 0.05).

CONCLUSIONS

It seems that antioxidant effect of thymoquinone could protect damage of liver parameters against morphine toxicity.