The effects of antihypertensive drugs on chromium status, glucose metabolism, and antioxidant and inflammatory indices in spontaneously hypertensive rats

Amlodipine alleviates cisplatin-induced nephrotoxicity in rats through gamma-glutamyl transpeptidase (GGT) enzyme inhibition, associated with regulation of Nrf2/HO-1, MAPK/NF-κB, and Bax/Bcl-2 signaling

BACKGROUND

The therapeutic utility of the effective chemotherapeutic agent cisplatin is hampered by its nephrotoxic effect. We aimed from the current study to examine the possible protective effects of amlodipine through gamma-glutamyl transpeptidase (GGT) enzyme inhibition against cisplatin nephrotoxicity.

METHODS

Amlodipine (5 mg/kg, po) was administered to rats for 14 successive days. On the 10th day, nephrotoxicity was induced by a single dose of cisplatin (6.5 mg/kg, ip). On the last day, blood samples were collected for estimation of kidney function, while kidney samples were used for determination of GGT activity, oxidative stress, inflammatory, and apoptotic markers, along with histopathological evaluation.

RESULTS

Amlodipine alleviated renal injury that was manifested by significantly diminished serum creatinine and blood urea nitrogen levels, compared to cisplatin group. Amlodipine inhibited GGT enzyme, which participates in the metabolism of extracellular glutathione (GSH) and platinum-GSH-conjugates to a reactive toxic thiol. Besides, amlodipine diminished mRNA expression of NADPH oxidase in the kidney, while enhanced the anti-oxidant defense by activating Nrf2/HO-1 signaling. Additionally, it showed marked anti-inflammatory response by reducing expressions of p38 mitogen-activated protein kinase (p38 MAPK) and nuclear factor-kappa B (NF-κB), with subsequent down-regulation of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and vascular cell adhesion molecule-1 (VCAM-1). Moreover, amlodipine reduced Bax/Bcl-2 ratio and elevated hepatocyte growth factor (HGF), thus favoring renal cell survival.

CONCLUSIONS

Effective GGT inhibition by amlodipine associated with enhancement of anti-oxidant defense and suppression of inflammatory signaling and apoptosis support our suggestion that amlodipine could replace toxic GGT inhibitors in protection against cisplatin nephrotoxicity.

Poor Glycaemic Control Is Associated with Increased Lipid Peroxidation and Glutathione Peroxidase Activity in Type 2 Diabetes Patients

Glycaemic control is the main focus of managing diabetes and its complications. Hyperglycaemia induces oxidative stress favouring cellular damage and subsequent diabetic complications. The present study was conducted to compare the plasma total antioxidant capacity (TAC) and individual antioxidant marker antioxidant status of type 2 diabetics (T2D) with good ((+) GC) and poor ((-) GC) glycaemic control with prediabetic (PDM) and normoglycaemic (NG) individuals. T2D (n = 147), PDM (n = 47), and NGC (n = 106) were recruited as subjects. T2D and PDM had lower plasma TAG than NG subjects. T2D and PDM had significantly higher GPx activity and plasma MDA concentrations than NG. PDM showed the highest SOD activity. T2D (-) GC showed significantly elevated GPx activity and higher MDA level and significantly lower SOD activity among all study groups. Lower plasma TAC and higher plasma MDA indicate the presence of oxidative stress in T2D and PDM. Elevated GPx activity in T2D, PDM, and particularly in T2D (-) GC suggests a compensatory response to counteract excess lipid peroxidation in the hyperglycaemic state. Decline in SOD activity advocates the presence of glycation and excess lipid peroxidation in T2D.

Diuretics, Ca-Antagonists, and Angiotensin-Converting Enzyme Inhibitors Affect Zinc Status in Hypertensive Patients on Monotherapy: A Randomized Trial

Background: Antihypertensive drugs affect mineral metabolism, inflammation, and the oxidative state. The aim of this study was to evaluate the effects of antihypertensive monopharmacotherapy with diuretics, β-blockers, calcium antagonists (Ca-antagonists), angiotensin-converting enzyme inhibitors (ACE-I), and angiotensin II receptor antagonists (ARBs) on zinc (Zn), iron (Fe), and copper (Cu) status, parameters of oxidative and inflammatory states, and glucose and lipid metabolism in patients with newly diagnosed primary arterial hypertension (AH). Methods: Ninety-eight hypertensive subjects received diuretics, β-blockers, Ca-antagonists, ACE-I, or ARB for three months. Zn, Fe, and Cu concentrations were determined in blood, urine, and hair. Results: A decrease in zinc serum and erythrocyte concentration and an increase in zinc urine concentration were registered after diuretic administration. Ca-antagonists led to a decrease in erythrocyte zinc concentration. A decrease in serum zinc concentration was observed after ACE-I. A decrease in triglyceride serum concentration was noted after ACE-I therapy, and a decrease in tumor necrosis factor-α serum concentration was seen following administration of Ca-antagonists. Hypotensive drugs led to decreases in catalase and superoxide dismutase serum concentrations. Conclusions: Three-months of monotherapy with diuretics, Ca-antagonists, or ACE-I impairs zinc status in patients with newly diagnosed primary AH. Antihypertensive monopharmacotherapy and zinc metabolism alterations affect lipid metabolism, the oxidative state, and the inflammatory state.

Effect of hypotensive therapy combined with modified diet or zinc supplementation on biochemical parameters and mineral status in hypertensive patients

BACKGROUND

Hypotensive therapy leads to a number of trace elements metabolism disturbances. Zinc balance is frequently affected by antihypertensive treatment.

AIM

To evaluate the effect of a hypotensive treatment, modified diet and zinc supplementation on mineral status and selected biochemical parameters in newly diagnosed hypertensive patients on monotherapy.

METHODS

In the first stage, arterial hypertension in ninety-eight human subjects was diagnosed. In the second stage, antihypertensive monopharmacotherapy was implemented. In the third stage, patients were randomized into three groups and continued antihypertensive monotherapy: group D received an optimal-mineral-content diet, group S received zinc supplementation, and group C had no changes in diet or zinc supplementation. Iron, zinc, and copper concentrations in serum, erythrocytes, urine, and hair were determined. Lipids, glucose, ceruloplasmin, ferritin, albumin, C-reactive protein (CRP), tumor necrosis factor α (TNF-α), nitric oxide (NO), superoxide dismutase (SOD) and catalase (CAT) were assayed in serum.

RESULTS

Antihypertensive monotherapy decreased zinc concentration in serum and erythrocytes and increased the level of zinc in urine, decreased CAT and SOD activity, TNF-α concentration in serum, and increased the level of NO in the serum. Zinc supply led to an increase in zinc concentration in serum, erythrocytes, and hair (in group S only). In the groups with higher zinc intake, decreased glucose concentration in the serum was observed. Significant correlation was seen between the zinc and glucose serum concentrations.

CONCLUSION

Hypotensive drugs disturb zinc status in newly diagnosed hypertensive patients. Antihypertensive monotherapy combined with increased zinc supply in the diet or supplementation favorably modify zinc homeostasis and regulate glucose status without blood pressure affecting in patients with hypertension.

[Efficiency of triple antihypertensive therapy in patients with uncontrolled hypertension and depressive disorders]

AIM

To evaluate the efficiency of triple antihypertensive therapy in patients with uncontrolled hypertension and depressive disorders (DD).

MATERIAL AND METHODS

153 patients with uncontrolled hypertension were examined, of whom 82 patients were diagnosed with mild and moderate DD. A combination of perindopril 10 mg/day, indapamide SR 1.5 mg/day, and amlodipine at an initial dose of 5 mg/day was given to patients with hypertension and DD. After 4 weeks of treatment, if target blood pressure (BP) levels could not be achieved, the dose of amlodipine was increased up to 10 mg/day. General clinical examination and 24-hour BP monitoring (BPM) were performed in all the patients at baseline and in the patients with DD also after 24 weeks of therapy. The traditional measures of the diurnal BP profile, as well as the parameters characterizing arterial stiffness and central aortic pressure (CAP) were estimated.

RESULTS

After 8 weeks of therapy, target BP levels were recorded in 63 (76.8%) patients. After 24 weeks of treatment, the hypertensive patients with DD showed significant positive changes in all the investigated 24-hour BPM parameters and normalization of the diurnal BP profile in 65.1% of cases. During the treatment, there were significant decreases in pulse wave velocity, brachial arterial and aortic augmentation indices, aortic systolic and diastolic pressures, and mean aortic BP and an increase in the velocity of the reflected wave.

CONCLUSION

Triple therapy, including perindopril, indapamide SR, and amlodipine, contributed to the achievement of target BP levels in the majority of hypertensive patients with DD, with significant positive changes in all 24-hour BPM parameters, optimization of the diurnal BP profile in most patients, clinically significant improvement of the parameters that characterize arterial stiffness and CAP.

An evaluation of the protective role of vitamin C in reactive oxygen species-induced hepatotoxicity due to hexavalent chromium in vitro and in vivo

Backgroud

Drinking water contamination with hexavalent chromium [Cr (VI)] has become one of the most serious public health problems, thus the investigation of Cr (VI)-induced hepatotoxicity has attracted much attention in recent years.

Methods

In the present study, by determining the indices of hepatotoxicity induced by Cr (VI), the source of accumulated reactive oxygen species (ROS), and the protective effect of the antioxidant Vitamin C (Vit C), we explored the mechanisms involved in Cr (VI)-induced hepatotoxicity in vitro and in vivo.

Results

We found Cr (VI) caused hepatotoxicity characterized by the alterations of several enzymatic and cytokine markers including aspartate aminotransferase (AST), alanine aminotransferase (ALT), interleukine-1β (IL-1β), and tumor necrosis factor-α (TNF-α), etc. ROS production after Cr (VI) exposure was origins from the inhibition of electron transfer chain (ETC) and antioxidant system. Vit C inhibited ROS accumulation thus protected against Cr (VI)-induced hepatotoxicity in L-02 hepatocytes and in the rat model.

Conclusions

We concluded that ROS played a role in Cr (VI)-induced hepatotoxicity and Vit C exhibited protective effect. Our current data provides important clues for studying the mechanisms involved in Cr (VI)-induced liver injury, and may be of great help to develop therapeutic strategies for prevention and treatment of liver diseases involving ROS accumulation for occupational exposure population.

Intranasal Chromium Induces Acute Brain and Lung Injuries in Rats: Assessment of Different Potential Hazardous Effects of Environmental and Occupational Exposure to Chromium and Introduction of a Novel Pharmacological and Toxicological Animal Model

Chromium (Cr) is used in many industries and it is widely distributed in the environment. Exposure to Cr dust has been reported among workers at these industries. Beside its hazardous effects on the lungs, brain injury could be induced, as the absorption of substances through the nasal membrane has been found to provide them a direct delivery to the brain. We investigated the distribution and the effects of Cr in both brain and lung following the intranasal instillation of potassium dichromate (inPDC) in rats. Simultaneously, we used the common intraperitoneal (ipPDC) rat model of acute Cr-toxicity for comparison. Thirty male Wistar rats were randomly allocated into five groups (n = 6); each received a single dose of saline, ipPDC (15 mg/kg), or inPDC in three dose levels: 0.5, 1, or 2 mg/kg. Locomotor activity was assessed before and 24 h after PDC administration, then, the lungs and brain were collected for biochemical, histopathological, and immunohistochemical investigations. Treatment of rats with ipPDC resulted in a recognition of 36% and 31% of the injected dose of Cr in the brain and lung tissues, respectively. In inPDC-treated rats, targeting the brain by Cr was increased in a dose-dependent manner to reach 46% of the instilled dose in the group treated with the highest dose. Moreover, only this high dose of inPDC resulted in a delivery of a significant concentration of Cr, which represented 42% of the instilled dose, to the lungs. The uppermost alteration in the rats locomotor activity as well as in the brain and lung histopathological features and contents of oxidative stress biomarkers, interleukin-1β (IL-1β), phosphorylated protein kinase B (PKB), and cyclooxygenase 2 (COX-2) were observed in the rats treated with inPDC (2 mg/kg). The findings revealed that these toxic manifestations were directly proportional to the delivered concentration of Cr to the tissue. In conclusion, the study showed that a comparably higher concentrations of Cr and more elevated levels of oxidative stress and inflammatory markers were observed in brain and lung tissues of rats subjected to inPDC in a dose that is just 0.13 that of ipPDC dose commonly used in Cr-induced toxicity studies. Therefore, the study suggests a high risk of brain-targeting injury among individuals environmentally or occupationally exposed to Cr dust, even in low doses, and an additional risk of lung injury with higher Cr concentrations. Moreover, the study introduces inPDC (2 mg/kg)-instillation as a new experimental animal model suitable to study the acute brain and lung toxicities induced by intranasal exposure to Cr compounds.