Serum heat shock protein 70 levels in patients with myocardial infarction: a descriptive observational study

Abstract

Background: Heat shock protein 70 (HSP70) is a molecular chaperone involved in cellular stress responses, protein homeostasis, and inflammatory signalling. Myocardial infarction may influence circulating HSP70 concentrations through cellular stress and myocardial injury. Age and associated comorbidities may also contribute to variations in circulating HSP70. The objective is to describe serum HSP70 concentrations in patients with myocardial infarction and explore their distribution according to age and comorbidity status. Materials and Methods: This hospital-based descriptive observational study included 47 patients diagnosed with ST-elevation myocardial infarction (STEMI) or non-ST-elevation myocardial infarction (NSTEMI). Participants were recruited consecutively between January 2026 and June 2026 at Shri B. M. Patil Medical College, Hospital and Research Centre, Vijayapura, Karnataka, India. Serum was separated by centrifugation at 3000 rpm for 3 minutes and stored at −80°C until analysis. HSP70 concentrations were measured using a commercial human HSP70 enzyme-linked immunosorbent assay (ELISA) kit (Chongqing Biospes; catalogue number BZEK2956), with absorbance measured at 450 nm and concentrations determined using a calibration curve. Participants were categorised into three age groups (30–44, 45–59, and 60–80 years) and four comorbidity groups based on the documented presence or absence of hypertension and diabetes mellitus. Statistical analyses were performed using IBM SPSS Statistics version 31. Results: A total of 47 participants were included, with a mean age of 57.47 ± 13.44 years. STEMI accounted for 66.0% of participants and NSTEMI for 34.0%. The overall mean serum HSP70 concentration was 183.43 ± 61.99 pg/mL. Mean concentrations across the 30–44, 45–59, and 60–80-year age groups were 203.80 ± 73.00, 179.08 ± 73.23, and 177.06 ± 46.40 pg/mL, respectively; the difference was not statistically significant (p = 0.511). The correlation between age and HSP70 concentration was also not statistically significant (Spearman’s rₛ = −0.099, p = 0.510). Mean concentrations across the groups with neither hypertension nor diabetes, hypertension alone, diabetes alone, and both conditions were 169.29 ± 56.50, 165.19 ± 57.91, 187.26 ± 71.73, and 206.16 ± 59.68 pg/mL, respectively. The overall difference among these groups was not statistically significant (p = 0.331). Conclusion: The study describes serum HSP70 concentrations in patients with myocardial infarction and explores their distribution according to age and comorbidity status. No statistically significant differences were observed across the age or comorbidity groups in the analysis. Further studies involving larger populations, appropriate comparison groups, and serial measurements are needed to clarify the clinical significance of circulating HSP70 in myocardial infarction.