Insulin or insulin-like studies on unicellular organisms: a review

Abstract

This paper presents a review of studies about insulin and insulin-like substances in prokaryotes, eukaryotes and fungi have been published over the last two decades, constituting an updating of our previous review (1988) which included references to invertebrate insulin or insulin-like substances both in uni-and pluricellular Monera, Protoctista, Fungii and Animal species. This present article reviews experiments and evidence obtained using modern techniques in the understanding of molecule evolution and behaviour, which confirm its very ancient molecular structure origin. The involvement of insulin-like and related material in signalling biological pathwayand modulator effects is also reported.

Effect of naringerin on biochemical parameters in the streptozotocin-induced diabetic rats

“…After insulin became available, evidence emerged suggesting that human diabetes mellitus has a multifactotial aetiology. Insulin was the principle hypoglycaemic medication used in diabetes mellitus treatment (Souza and López, 2004). In order to discover other hypoglycaemic agents, many investigations have been performed in traditional medicine testing eventual hypoglycaemic naturals (Keenoy et al, 2005;Bonnefont et al, 2004).…”

Screening microorganisms for insulin binding reveals binding by Burkholderia multivorans and Burkholderia cenocepacia and novel attachment of insulin to Aeromonas salmonicida via the A-layer

“…The initial binding experiments used a concentration of insulin that was much higher than the physiological concentration, but in‐line with what previous workers had used (Christopher & Sundermann, ; Souza & López, ). These experiments were repeated with insulin‐binding positive bacteria using insulin at a normal physiological concentration.…”

“…Hormone‐binding proteins have been previously found in various types of microorganism, bacteria, fungi and protozoa (Souza & López, ). In the current study, 45 microbial species were screened for the presence of cell surface components capable of binding with the hormone insulin.…”

“…Since 1970, many studies have shown the presence of insulin‐like molecules and insulin‐like receptors in some protozoa, bacteria and fungi (Collier et al ., ; Dietz et al ., ; Jeromson et al ., ). The first observation was made with the fungus Neurospora crassa showing the existence of insulin‐binding sites with high affinity on the fungal cell surface (Fawell & Lenard, ; Souza & López, ). A study of the insulin‐binding protein (IBP) in N. crassa revealed that it is a signal transduction component mediating glucose metabolism (Fawell et al ., ), and an estimate of 10 3 insulin‐binding sites per cell was obtained (Kole et al ., ).…”

SCREENING OF PHOTOSYNTHETIC O2‐EVOLVING PROKARYOTES FOR AN INSULIN‐LIKE ANTIGEN1

“…A considerable number of reports on the presence of insulin‐like antigen in extracts from many different species ranging from unicellular prokaryotes and eukaryotes had been published (Souza and Lopez 2004). These molecules were detected by employing antibodies (raised against vertebrate insulin) and different chromatographic techniques.…”