Microencapsulation and Culture in Vitro of Rat Pinealocytes

Background Melatonin is a powerful anti-aging reagent for scavenging free radicals. However, the effect of exogenous melatonin on age-dependent diseases is uncertain. Immune rejection has limited xenotransplantation or allotransplantation of the pineal gland. The aim of this study was to assess cell viability and the function of rat pinealocytes encapsulated in APA capsules and offer experimental suggestions for pineal microencapsulation grafting to resist aging. Methods The pineal glands of neonatal rats were removed. Pinealocytes were isolated and encapsulated in APA microencapsulation and cultured. Morphological appearance of the microencapsulation was observed. Trypan blue staining and 5-HT immunocytochemical assay were used to detect cell viability and identify pinealocytes. The expression of AA-NAT mRNA was confirmed by RT-PCR. Melatonin release was measured and compared by HPLC. Results Both control and encapsulated pinealocyte cultures survived well. The majority of the encapsulated pinealocytes as well as unencapsulated cells remained 5-HT positive. No significant difference in melatonin secretion and the expression level of AA-NAT mRNA between encapsulated and unencapsulated pinealocytes was found. Conclusions Pinealocytes survive and remain functionally competent in vitro at least 2 weeks after microencapsulation.