Pretreatment with aqueous Moringa oleifera Lam. leaf extract prevents cadmium-induced hepatotoxicity by improving cellular antioxidant machinery and reducing cadmium accumulation.

Cadmium (Cd) is a highly harmful pollutant that poses a serious threat to human health. The liver is the primary organ for Cd accumulation, and Cd-induced hepatotoxicity has been shown to be strongly correlated with an oxidative imbalance in hepatocytes. Our previous studies in the eukaryotic model organism Saccharomyces cerevisiae revealed that not only co-treatment but also pretreatment with aqueous Moringa oleifera Lam. leaf extract (AMOLE) effectively mitigated Cd toxicity by reducing intracellular Cd accumulation and Cd-mediated oxidative stress. In this study, we therefore investigated the preventive effect of AMOLE against Cd toxicity in human HepG2 hepatocytes. The results showed that, similar to the case of the yeast model, pretreatment with AMOLE prior to Cd exposure also significantly inhibited Cd-induced oxidative stress in HepG2 cells. Untargeted LC-MS/MS-based metabolomic analysis of AMOLE revealed that its major phytochemical constituents were organic acids, particularly phenolic acids and carboxylic acids. Additionally, DPPH-HPTLC fingerprints suggested that quercetin and other flavonoids possibly contribute to the antioxidant activities of AMOLE. Based on our findings, it appears that pretreatment with AMOLE prevented Cd-induced hepatotoxicity via three possible mechanisms: i) direct elimination of free radicals by AMOLE antioxidant compounds; ii) upregulation of antioxidant defensive machinery (GPx1, and HO-1) via Nrf2 signaling cascade to improve cellular antioxidant capacity; and iii) reduction of intracellular Cd accumulation, probably by suppressing Cd uptake. These data strongly suggest the high potential of AMOLE for clinical utility in the prevention of Cd toxicity.

Preliminary Evidence of the Potent and Selective Adenosine A2B Receptor Antagonist PSB-603 in Reducing Obesity and Some of Its Associated Metabolic Disorders in Mice.

The adenosine A2A and A2B receptors are promising therapeutic targets in the treatment of obesity and diabetes since the agonists and antagonists of these receptors have the potential to positively affect metabolic disorders. The present study investigated the link between body weight reduction, glucose homeostasis, and anti-inflammatory activity induced by a highly potent and specific adenosine A2B receptor antagonist, compound PSB-603. Mice were fed a high-fat diet for 14 weeks, and after 12 weeks, they were treated for 14 days intraperitoneally with the test compound. The A1/A2A/A2B receptor antagonist theophylline was used as a reference. Following two weeks of treatment, different biochemical parameters were determined, including total cholesterol, triglycerides, glucose, TNF-α, and IL-6 blood levels, as well as glucose and insulin tolerance. To avoid false positive results, mouse locomotor and spontaneous activities were assessed. Both theophylline and PSB-603 significantly reduced body weight in obese mice. Both compounds had no effects on glucose levels in the obese state; however, PSB-603, contrary to theophylline, significantly reduced triglycerides and total cholesterol blood levels. Thus, our observations showed that selective A2B adenosine receptor blockade has a more favourable effect on the lipid profile than nonselective inhibition.

Hydroalcoholic Leaf Extract of Isatis tinctoria L. via Antioxidative and Anti-Inflammatory Effects Reduces Stress-Induced Behavioral and Cellular Disorders in Mice.

Stress that can occur at different levels of a person's life can cause and exacerbate various diseases. Oxidative stress and inflammation underlie this process at the cellular level. There is an urgent need to identify new and more effective therapeutic targets for the treatment of stress-induced behavioral disorders and specific drugs that affect these targets. Isatis tinctoria L. is a herbaceous species in the Brassicaceae family. Due to its potential antioxidant, nitric oxide- (NO-) inhibiting, anti-inflammatory, and neuroprotective properties, I. tinctoria could be used to treat depression, anxiety, and stress resistance. Hence, the present study is aimed at delineating whether administration of I. tinctoria leaf extract may improve stress-induced disorders in mice. A set of four behavioral tests was selected that together are suitable for phenotyping acute restraint stress-associated behaviors in mice, namely locomotor activity, social integration, dark/light box, and splash tests. The plasma and brains were collected. A brain-derived neurotrophic factor, tumor necrosis factor-alpha, C-reactive protein, corticosterone, NO, reactive oxygen species levels, superoxide dismutase and catalase activity, and ferric-reducing antioxidant power were measured. In mice stressed by immobilization, decreased locomotor activity, anxiety-like behavior, and contact with other individuals were observed, as well as increased oxidative stress and increased levels of nitric oxide in the brain and plasma C-reactive protein. A single administration of I. tinctoria leaf extract was able to reverse the behavioral response to restraint by a mechanism partially dependent on the modulation of oxidative stress, neuroinflammation, and NO reduction. In conclusion, Isatis tinctoria hydroalcoholic leaf extract can reduce stress-induced behavioral disturbances by regulating neurooxidative, neuronitrosative, and neuroimmune pathways. Therefore, it could be recommended for further research on clinical efficacy in depression and anxiety disorder treatment.

Influence of betahistine repeated administration on a weight gain and selected metabolic parameters in the model of excessive eating in rats.

It is important to search for a promising therapeutic target or small molecules that can control excessive eating since limiting the intake of foods, especially tasty ones, could be effective in the treatment or prevention of obesity. Some studies indicate betahistine as an unique drug having the ability to ameliorate, for example, antipsychotic-induced weight gain. This study aimed to determine whether repeated administration of betahistine (histamine H1R agonist and H3R antagonist) could be beneficial in reducing the intake of tasty foods or the body's response to overeating via mechanisms such as by influencing the levels of hormones involved in the regulation of food intake or the levels of selected metabolic parameters. Studies were performed in the excessive eating model in rats, which perfectly illustrates the harmful high-caloric intake from freely available tasty products rich in sugar and fat. Our results indicated that repeated administration of betahistine to rats caused lower gain of body mass compared to the control rats fed palatable feed. Interestingly, betahistine treatment increased the consumption of cheese, which is a source of histamine. Although betahistine did not prevent the development of metabolic disorders, such as reduced glucose tolerance, in test animals, it significantly increased the level of high-density lipoprotein cholesterol, which could certainly be considered beneficial. Further studies should be conducted to investigate the effect of repeated administration of betahistine on satiety, gastrointestinal disorders, and the preference for histamine-containing foods.

PSB 603 - a known selective adenosine A2B receptor antagonist - has anti-inflammatory activity in mice.

A2B adenosine receptors are present in a wide spectrum of tissues, especially on cells of the immune system. Since these particular receptors have the lowest, of all adenosine receptor subtypes, affinity for adenosine they are believed to play a special role in immunological processes associated with elevated adenosine levels such as inflammation. The aim of this preliminary study was to determine the potential anti-inflammatory properties of compound PSB-603, a potent and selective adenosine A2B receptor antagonist, in two different experimental models of local and systemic inflammation. In a model of inflammation induced by local carrageenan administration paw edema was measured using a pletysmometer. Additionally, levels of C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α) and reactive oxygen species (ROS) were determined in the inflamed paw. Using the mouse model of peripheral inflammation induced by intraperitoneal (ip) administration of zymosan A, the influence of the A2B antagonist on the infiltration of neutrophils into the peritoneum and its effect on the plasma levels of CRP, TNF-α, and IL-6 were investigated. The results showed that PSB-603 administered at a dose of 5 mg/kg b.w. ip significantly reduced inflammation in both tested models. Particularly, it significantly decreased levels of the inflammatory cytokines IL-6, TNF-α and of ROS in the inflamed paw and reduced inflammation of the peritoneum by significantly decreasing the infiltration of leukocytes. Additionally, in the latter model, no statistically significant difference was observed in the CRP level between the control group without inflammation and the group which has been treated with the PSB-603 compound. Thus, the results may indicate the anti-inflammatory activity of adenosine A2B receptor antagonists in two different models of inflammation.

KD-64-A new selective A2A adenosine receptor antagonist has anti-inflammatory activity but contrary to the non-selective antagonist-Caffeine does not reduce diet-induced obesity in mice.

The A2 adenosine receptors play an important role, among others, in the regulation of inflammatory process and glucose homeostasis in diabetes and obesity. Thus, the presented project evaluated of influence of the selective antagonist of A2A adenosine receptor-KD-64 as compared to the known non-selective antagonist-caffeine on these two particular processes. Two different inflammation models were induced namely local and systemic inflammation. Obesity was induced in mice by high-fat diet and the tested compounds (KD-64 and caffeine) were administrated for 21 days. KD-64 showed anti-inflammatory effect in both tested inflammation models and administered at the same dose as ketoprofen exerted stronger effect than this reference compound. Elevated levels of IL-6 and TNF-α observed in obese control mice were significantly lowered by the administration of KD-64 and were similar to the values observed in control non-obese mice. Interestingly, caffeine increased the levels of these parameters. In contrast to caffeine which had no influence on AlaT activity, KD-64 administration significantly lowered AlaT activity in the obese mice. Although, contrary to caffeine, KD-64 did not reduce diet-induced obesity in mice, it improved glucose tolerance. Thus, the activity of the selective adenosine A2A receptor antagonist was quite different from that of the non-selective.

KSK19 - Novel histamine H3 receptor ligand reduces body weight in diet induced obese mice.

AIMS: Histamine H3 receptors ligands act anorectic by blocking the H3 autoreceptors in the CNS, that results in increased synthesis and disinhibition of histamine release. Histamine further influencing H1 receptors participates in the leptin-dependent inhibition of food intake. It also affects the peripheral metabolism by increasing white adipose tissue lipolysis. Thus, ligands such as KSK19 with significant antagonistic properties at the H3 receptor might serve as an useful treatment for obesity. MATERIALS AND METHODS: To induce obesity, female CD-1 mice were fed a high-fat diet for 14 weeks. The test compound at the doses of 10 or 15 mg/kg, i.p. was administrated for 21 days. Glucose and insulin tolerance tests was performed at the beginning of week 15. At the end of study, amount of intraperitoneal fat pads, AlAT, IL-6 and TNF-α plasma levels were determined. RESULTS: Animals fed with high-fat diet and treated with test compound at the dose of 15 mg/kg showed significantly less weight gain, than mice from the control group. The use of KSK19 for 21 days in obese mice also significantly improved glucose tolerance and insulin resistance. In the tested doses KSK19 did not affect locomotor activity neither in lean nor in obese mice after single i.p. administration, but spontaneous activity increased during three hour after twentieth administrations. CONCLUSION: KSK19 is a strong, selective histamine H3 receptor antagonist with a favorable influence on body weight after multiple administration at the dose of 15 mg/kg. Moreover it significantly improves glucose tolerance.