A systematic review of literature on Insulin-like growth factor-2-mediated hypoglycaemia in non-islet cell tumours

INTRODUCTION

Insulin-like growth factor-2 (IGF-2)-mediated hypoglycemia is a rare yet clinically significant entity with considerable morbidity and mortality. Existing literature is limited and fails to offer a comprehensive understanding of its clinical trajectory, management and prognostication.

METHODS

Systematic review of English-language articles reporting primary patient data on IMH was searched using electronic databases (PubMed, Scopus and Embase) from any date up to 21 December 2022. Data were analysed in STATA-16.

RESULTS

The systematic review contains 172 studies, including 1 Randomised controlled trial, 1 prospective observational study, 5 retrospective observational studies, 150 case reports, 11 case series and 4 conference abstracts. A total of 233 patients were analysed, averaging 60.6 ± 17.1 years in age, with comparable proportions of males and females. The commonest tumours associated with Insulin-like Growth Factor-2-mediated hypoglycaemia were fibrous tumours (N = 124, 53.2%), followed by non-fibrous tumours originating from the liver (N = 21, 9%), hemangiopericytomas (N = 20, 8.5%) and mesotheliomas (N = 11, 4.7%). Hypoglycaemia was the presenting feature of NICT in 42% of cases. Predominant clinical features included loss of consciousness (26.7%) and confusion (21%). The mean IGF-2 and IGF-1 levels were 882.3 ± 630.6 ng/dL and 41.8 ± 47.8, respectively, with no significant correlation between these levels and patient outcomes. Surgical removal was the most employed treatment modality (47.2%), followed by medication therapy. The recovery rate was 77%, with chronic liver disease (CLD) significantly associated with a poor outcome (OR: 7.23, P: 0.03). Tumours originating from fibrous tissues were significantly associated with recovery (p < .001). In the logistic regression model, CLD remained a significant predictor of poor outcomes.

CONCLUSION

This systematic review highlights that most non-islet-cell tumour-hypoglycaemia (NICTH) is due to fibrous tumours. NICTs demonstrate a variable prognosis, which is fair if originating from fibrous tissue. Management such as octreotide, corticosteroids, diazoxide, embolization, radiotherapy and surgical resection have disparate success rates.

Acetyl-L-carnitine rescues scopolamine-induced memory deficits by restoring insulin-like growth factor II via decreasing p53 oxidation

Alzheimer's disease (AD) is characterized by the cholinergic neurons loss and impairments of learning and memory. Scopolamine is common used to imitate AD pathological features and also causes an obvious oxidative stress. In this study, we found that intraperitoneal administration of supplementary acetyl-L-carnitine partially reverses the learning and memory defects induced by scopolamine. We also found that acetyl-L-carnitine reverses the impairment of long-term potentiation, dendritic abnormalities, and the impaired recruitment of synaptic protein. The beneficial effects of acetyl-L-carnitine may occur through amelioration of oxidative stress because it effectively decreases the levels of oxidative products and increases the activity of superoxide dismutase; this leads to a recovery in the suppressed activity of p53 caused oxidative stimuli, which in turn restores levels of insulin-like growth factor II, an important hormone for learning and memory. Our study provides the first evidence of the potential utility of acetyl-L-carnitine in treating the synaptic disorders prevalent in AD and other neurodegenerative diseases. This article is part of the Special Issue entitled 'The Synaptic Basis of Neurodegenerative Disorders'.