Science is still searching for readily available, cost-effective biomarkers to assess metabolic disorders occurring before the onset and during the development of type-2 diabetes (T2DM). The aim of the present study was to induce T2DM in rats through a high-fat diet, followed by a single administration of low dose streptozotocin (STZ), and make an assessment of the development of the disease. The rats were divided into two groups—experimental and control—and were monitored for a period of 10 days. Changes in anthropometric parameters, glucose, insulin, lipids, uric acid, advanced oxidation protein products (AOPP), as well as the histological changes in the liver and pancreas, were recorded. To assess insulin resistance, we used the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) and beta cell function (HOMA-β) and visceral obesity—adiposity index (AI). The data demonstrate that the increasing values of glucose, HOMA-IR, AI, total cholesterol, triacylglycerols, low- and very-low-density lipoproteins are important markers of the pre-diabetic state. The stable hyperglycemia and increased levels of TC, TG, VLDL, LDL, uric acid and AOPP in experimental rats strongly suggest the development of T2DM. HOMA-IR, HOMA-β, AI, and uric acid are reliable criteria for T2DM in rats.

Aminoglycoside antibiotics and gentamicin (GN), in particular, are still widely used in clinical practice. It is a well-known fact that GN causes nephrotoxicity, and redox disturbances are discussed as a factor in its side effects. Recently, a new type of cell oxidative death, named ferroptosis, was discovered; it is associated with iron accumulation in the cell, glutathione (GSH) depletion and inactivation of glutathione peroxidase-4 (GPX4), reactive oxygen species (ROS) increment with concomitant lipid peroxidation. In this regard, a possible connection between GN-induced renal damage, ferroptosis and the overall antioxidant status of the organism could be investigated. Moreover, due to its beneficial effects, GN is still one of the main choices as a therapeutic agent for several diseases, and the possible reduction of its side effects with the application of certain antioxidants will be of important clinical significance. The study was conducted with adult male white mice divided into several groups (n = 6). GN nephrotoxicity was induced by the administration of GN 100–200 mg/kg i.p. for 10 days. The control group received only saline. The other groups received either Vitamin E (400 mg/kg p.o.) or Silymarin (200 mg/kg p.o.) applied alone or together with GN for the same period. After the end of the study, the animals were sacrificed, and blood and tissue samples were taken for the assessment of biochemical parameters and antioxidant status, as well as routine and specific for GPX4 histochemistry examination. The experimental results indicate that GN-induced nephrotoxicity negatively modulates GPX4 activity and is associated with increased production of ROS and lipid peroxidation. The groups treated with antioxidants demonstrated preserved antioxidant status and better GPX4 activity. In conclusion, the inhibition of ROS production and especially the suppression of ferroptosis, could be of clinical potential and can be applied as a means of reducing the toxic effects of GN application.

Liver damage severity depends on both the dose and the exposure duration. Oxidative stress may increase the Ochratoxine-A (OTA) hepatotoxicity and many antioxidants may counteract toxic liver function. The present study aims to investigate the hepatoprotective potential of Azadirachta indicaA (A. indica; neem oil) seed oil to reduce acute oxidative disorders and residual OTA toxicity in a 28-day experimental model. The activity of antioxidant and hepatic enzymes, cytokines and the levels of oxidative stress biomarkers –MDA, GSPx, Hydroxiproline, GST, PCC, AGEs, PGC-1, and STIR-1 were analyzed by ELISA. The free radicals ROS and RNS levels were measured by EPR. The protective effects were studied in BALB/C mice treated with A. indica seed oil (170 mg/kg), alone and in combination with OTA (1.25 mg/kg), by gavage daily for 28 days. At the end of the experiment, mice treated with OTA showed changes in liver and antioxidant enzymes, and oxidative stress parameters in the liver and blood. A. indica oil significantly reduced oxidative stress and lipid peroxidation compared to the OTA group. In addition, the hepatic histological evaluation showed significant adipose tissue accumulation in OTA-treated tissues, while treatment with 170 mg/kg A. indica oil showed moderate adipose tissue accumulation.

The protective effects of the herbal feed supplements Silybum marianum, Silymarin, Withania somnifera, and Centella asiatica against ochratoxin A (OTA) toxicity were studied in 48 New Zealand White rabbits (37-day-old) during an 80-day experiment. OTA was given at 2 ppm, whereas Silybum marianum, Silymarin, Withania somnifera, and Centella asiatica were given at feed levels of 5000 ppm, 25,000 ppm, 4000 ppm, and 4600 ppm, respectively. All rabbits were immunized against Rabbit Hemorrhagic Disease Virus (RHDV). OTA was found to induce an immunosuppressive effect on the humoral immune response. Reliable protection against OTA-provoked immunosuppression by Silimarin and Withania somnifera was found. The OTA-induced immunosuppression was responsible for secondary bacterial infection (pasteurellosis) and the death of two rabbits from the OTA-exposed group and one rabbit each from the groups protected with Silybum marianum and Centella asiatica. A decreased body weight was found in rabbits exposed to OTA, but the decrease was slighter in the rabbits protected with herbal supplements. The target organs damaged by OTA exposure were the liver, kidneys, and spleen, while weaker lesions were found in other internal organs, except in the cases of secondary pasteurellosis, in which the strongest damage was found in the lung. All investigated herbal supplements appeared to have stronger protective effects against OTA-induced damage to the kidneys and liver, with slightly protective effects observed in the lungs, myocardium, spleen, brain, intestine, testicles, and ovaries.

Silymarin—a standardized extract from the seeds of milk thistle (Silybum marianum L. Gaertn.)—is mainly used for the treatment of hepatitis and other liver diseases. In recent years, the attention of researchers has been directed to its use in dermatology and wound treatment. Despite the promising results, there are still many unresolved issues in this area. The aim of the present study is to develop and characterize hydrogel chitosan–pectin films containing silymarin as an active ingredient with potential medical application. Six variants of hydrogel films (control and silymarin-loaded) were obtained from chitosan and pectin solutions by the casting method and analyzed in terms of their physicochemical, structural, mechanical and optical properties, as well as the in vitro dissolution profile of silymarin. The highest tensile strength was measured for the chitosan-based films—23.35 ± 1.74 MPa (control) and 22.01 ± 2.67 MPa (silymarin-loaded), while the barrier properties to UV and visible light were the strongest for chitosan–pectin films with silymarin. The antioxidant potential of the films was determined by DPPH assay and it was found that the variants with silymarin have over 20 times higher antioxidant activity (from 2.020 ± 0.048 to 2.106 ± 0.190 mg TE/g) than the corresponding controls. The results showed that chitosan–pectin films with incorporated silymarin could find application as potential hydrogel dressings in the therapy of wounds and superficial burns.