Proinflammatory biomarkers have been increasingly used in epidemiologic and intervention studies over the past decades to evaluate and identify an association of systemic inflammation with cardiovascular diseases. Although there is a strong correlation between the elevated level of inflammatory biomarkers and the pathology of various cardiovascular diseases, the mechanisms of the underlying cause are unclear. Identification of pro-inflammatory biomarkers such as cytokines, chemokines, acute phase proteins, and other soluble immune factors can help in the early diagnosis of disease. The presence of certain confounding factors such as variations in age, sex, socio-economic status, body mass index, medication and other substance use, and medical illness, as well as inconsistencies in methodological practices such as sample collection, assaying, and data cleaning and transformation, may contribute to variations in results. The purpose of the review is to identify and summarize the effect of demographic factors, epidemiological factors, medication use, and analytical and pre-analytical factors with a panel of inflammatory biomarkers CRP, IL-1b, IL-6, TNFa, and the soluble TNF receptors on the concentration of these inflammatory biomarkers in serum.

The purpose of this study was to evaluate the protective role of soursop leaves and avocado seed extract, single or in combination against isoproterenol (ISO)-induced myocardial infarction (MI) in Male Wistar rats. The extracts were given orally for 15 days, while ISO 85 mg/kg were administered intraperitoneally twice at an interval 24h. The measured parameters were serum levels of biomarkers of alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), creatine kinase (CK), and creatine kinase-MB (CK-MB). Furthermore, histopathology was done to observe the integrity of the myocardial cell membrane. The results showed that pretreatment of single extract of soursop leaves (150 mg/kg) and avocado seeds (150 mg/kg) did not significantly inhibit the effects of ISO on ALT, AST, LDH, CK, and CK-MB. Meanwhile, pretreatment of the combination of soursop leaf ethanol extract and avocado seeds 75-75 mg/kg b.w. inhibited the increase of ALT, AST, LDH, CK, and CK-MB biomarkers level (5.4%; 27.08%; 35.68%; 14.29%; and 43.79%, respectively) significantly as compared to the ISO control group. The combination extract at doses of 75 mg/kg b.w. each could maintain the integrity of the myocardial cell membrane upon ISO administration. Overall, the cardioprotective activity of this extract combination of soursop leaf ethanol extract and avocado seeds at a dose of 75 mg/kg each was synergistic.