Curcumin ameliorates experimental autoimmune acute myocarditis in rats as evidenced by decrease in thioredoxin immunoreactivity

This study was performed to investigate the effect of curcumin on cardiac myosin-induced autoimmune myocarditis in rats and the change in thioredoxin (TRX) immunoreactivity in cardiomyocytes following curcumin treatment. Twenty-four six-week-old male Wistar rats were randomly allocated into 4 groups of 6 rats each. Group I received neither curcumin nor myosin. Group II received an oral solution of 1 g/kg/day of curcumin daily, from day 1 to day 21. To induce myocarditis, animals of both group III and group IV were injected by 1 mg of porcine cardiac myosin on days 1 and 8. In addition, animals of group IV received an oral solution of 1 g/kg/day of curcumin daily, from day 1 to day 21. Serum levels of creatine phosphokinase, troponin-T, tumour necrosis factor-alpha and interleukin-6 were estimated. Hearts were processed for histopathological and immunohistochemical studies. Serum biomarkers levels were significantly increased in myocarditis group as compared to other groups. The intake of curcumin significantly reduced the deviation in these markers. Sections of the wall of the heart from myocarditis group were characterised by inflammatory cell infiltration. Most of cardiomyocytes showed pyknotic nuclei and increased sarcoplasmic eosinophilia with strong immunoreactivity for TRX. Sections from myocarditis-curcumin group showed normal architecture with moderate immunoreactivity for TRX. The present study demonstrated that curcumin ameliorates acute myocarditis in rats and encouraged the estimation of serum level of TRX as a relevant indicator for the evaluation of the progress of acute myocarditis

Collagen types I and II distribution: a relevant indicator for the functional properties of articular cartilage in immobilised and remobilised rabbit knee joints

The objective of the present work was to study changes in collagen type I and type II distribution in the articular cartilage of immobilised and remobilised rabbit knee joints. Twenty-four adult male rabbits were divided into three groups. One of the groups was a control group with free movement. The right knee joints of animals of the other two groups were immobilised for 4 weeks, followed by a period of 10 weeks of remobilisation for animals of group 3. Collagen type I and type II in the articular cartilage of tibial medial condyle of the right knee joint were estimated immunohistochemically in all groups. A degenerative process was evident after 4 weeks of immobilisation of rabbit knee joint leading to a partial shift in the density of collagen composition from type II to type I. After a period of 10 weeks of remobilisation, regenerative processes, evidenced by a restoration of collagen type II to normal, proceeded on top of degenerative processes, evidenced by the significantly higher content of collagen type I compared with normal. The present study pointed to the importance of assessment of collagen distribution as a relevant indicator for the functional properties of articular cartilage in immobilised and remobilised joints

Lisinopril has a cardio-protective effect on experimental acute autoimmune myocarditis in rats

The present study investigated the effect of lisinopril on experimental autoimmune myocarditis (EAM) in rats, a histologically similar model to human acute myocarditis. Animals and methods. Twenty four, six week-old male Wistar rats were randomly allocated into 4 groups of 6 rats each. Group I received no treatment. Group II received lisinopril at a dose of 15 mg/kg/day suspended in 1 ml of 2% gum acacia daily, from day 1 to day 21. To induce myocarditis, animals of groups III and IV were injected by 1 mg of porcine cardiac myosin on days 1 and 8. In addition, animals of group IV received lisinopril in gum acacia daily, from day 1 to day 21. All rats were sacrificed on day 21. Serum levels of creatine phosphokinase, troponin-T, tumor necrosis factor-α and interleukin-6 were estimated. Hearts were processed for histopathological, as well as immunohistochemical study for thioredoxin (TRX) immunoreactivity. Results. The wall of hearts from rats of myocarditislisinopril group showed mild focal myocarditis and a significant decrease of the mean percentage of pyknotic nuclei in cardiomyocytes, coincident with a significant decrease in serum biomarkers levels and TRX immunoreactivity, compared to myocarditis group. Conclusion. The present study suggested a cardioprotective effect of lisinopril on acute EAM in rats, probably through a mechanism related to its suppressive effect on angiotensin II formation

Proanthocyanidin-Rich Date Seed Extract Protects Against Chemically Induced Hepatorenal Toxicity

A hydroacetone extract was prepared from seeds of Phoenix dactylifera L. var. Khalas, which is an industrial by-product of date processing. The proanthocyanidin nature of the extract (coded as DTX) was characterized by phytochemical and nuclear magnetic resonance (NMR) analyses. The total phenol/proanthocyanidin content and antioxidant activity of DTX were estimated by Folin–Ciocalteu, vanillin-sulfuric acid, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays, respectively. The hepatorenal protective activity of DTX was evaluated using CCl(4)-induced toxicity model in rats, in comparison with silymarin (SYL). Results of the histopathological examination and measurements of various hepatorenal serum indices and tissue biochemical markers demonstrated that DTX displayed marked protective potential against CCl(4)-induced liver and kidney injury at 100 mg/kg/rat. Relative to the control CCl(4)-intoxicated group, pretreatment with DTX significantly (P<.001) suppressed the elevated serum levels of alanine aminotransferase and aspartate aminotransferase (ALT and AST), alkaline phosphatase (ALP), γ-glutamyl transferase (GGT), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), bilirubin, creatinine, and calcium, whereas it significantly (P<.001) increased the diminished serum levels of high-density lipoprotein cholesterol (HDL-C) and total protein (TP). Moreover, DTX significantly decreased malondialdehyde (MDA) formation and increased TP synthesis in hepatorenal tissues compared with the intoxicated control. The improvement in biochemical parameters by DTX was observed in a dose-dependent manner and confirmed by restoration of normal histological features. The acute toxicity test of DTX in rats revealed safety of the extract. This study reveals that DTX enhances the recovery from xenobiotics-induced toxicity initiated by free radicals