Hepatic glycogenosis: An underdiagnosed complication of diabetes mellitus?

A Novel Therapeutic Strategy for Ameliorating Hyperglycemia-Induced Liver Injury via Overexpression of the Carboxyl Terminus of HSP70-Interacting Protein in Wharton's Jelly Mesenchymal Stem Cells

Diabetes is a widespread metabolic disorder that significantly affects modern society. The liver plays a vital role in metabolism; however, hyperglycemia can induce liver damage and disrupt its normal functions. Wharton's jelly mesenchymal stem cells (WJMSCs) engineered to express the carboxyl terminus of HSP70-interacting protein (CHIP) have demonstrated protective effects against hyperglycemia-induced damage in various organs. Nonetheless, the potential hepatoprotective effects and underlying mechanisms of these modified stem cells in diabetic livers remain unclear. Therefore, this study aimed to evaluate the efficacy of CHIP-transfected WJMSCs in mitigating hyperglycemia-induced hepatic injury in diabetic rats and to elucidate the associated protective mechanisms. Diabetic rats received tail vein injections of WJMSCs either overexpressing or silenced for CHIP. Seven weeks post-transplantation, all rats were sacrificed, and liver tissues were harvested for histological staining and Western blot analysis. The findings indicated that CHIP-overexpressing WJMSCs significantly reversed hyperglycemia-induced liver damage, reducing tissue injury, fibrosis, and glycogen deposition. These cells also alleviated hepatic inflammation and apoptosis. Moreover, they regulated oxidative stress pathways by lowering gp91-phox, Rac1, and phosphorylated PKCζ levels, while enhancing phosphorylated Nrf2 and SOD-2 expression. Additionally, the modified WJMSCs suppressed STAT3 activation and downregulated FOXO3a, suggesting a role in attenuating fibrosis and triglyceride accumulation in diabetic livers. Overall, CHIP-overexpressing WJMSCs reversed hyperglycemia-induced hepatic alterations by mitigating inflammation and oxidative stress while also modulating pathways related to fibrosis and lipid metabolism. These results highlight the therapeutic potential of CHIP-modified WJMSCs in managing diabetic liver complications and offer promising avenues for future treatment strategies.

Glycogen homeostasis and mitochondrial DNA expression require motor neuron to muscle TGF-β/Activin signaling in Drosophila

Maintaining metabolic homeostasis requires coordinated nutrient utilization between intracellular organelles and across multiple organ systems. Many organs rely heavily on mitochondria to generate (ATP) from glucose, or stored glycogen. Proteins required for ATP generation are encoded in both nuclear and mitochondrial DNA (mtDNA). We show that motoneuron to muscle signaling by the TGFβ/Activin family member Actβ positively regulates glycogen levels during Drosophila development. Remarkably, we find that levels of stored glycogen are unaffected by altering cytoplasmic glucose catabolism. Instead, loss of Actβ reduces levels of nuclearly encoded genes required for mtDNA replication, transcription, and translation and mtDNA levels. Direct RNAi knockdown of nuclearly encoded mtDNA expression factors in muscle also results in decreased glycogen stores. Lastly, expressing an activated form of the type I receptor Baboon in muscle restores both glycogen and mtDNA levels in actβ mutants, thereby confirming a direct link between Actβ signaling, glycogen homeostasis, and mtDNA expression factors.

Hepatic Glycogenosis: A Rare Complication of Type 1 Diabetes Mellitus

Type 1 diabetes mellitus (T1DM) is a common autoimmune pathology requiring lifelong insulin therapy. We report the case of a 12-year-old girl with T1DM admitted to Department C of the National Institute of Nutrition of Tunis for diabetic ketosis. She had suffered from T1DM for five years, with poor glycemic control (hemoglobin A1C = 10%) and poor therapeutic adherence. On examination, she had abdominal bloating with homogeneous hepatomegaly. Her height was 146 cm (less than the second percentile), her weight was 38 kg (less than the second percentile), and her body mass index was 17.8 kg/m². Tanner's stage was S1P1A1. Biological investigations showed mixed dyslipidemia, normal liver and renal functions, and normal thyroid-stimulating hormone levels. The aspartate aminotransferase/alanine aminotransferase ratio was 1.35. Ultrasound of the abdomen revealed hepatomegaly with a liver span of 19 cm. Based on the clinical history and investigations, Mauriac syndrome was the most likely diagnosis of our patient. A holistic multidisciplinary approach, in collaboration with the child psychiatrist, was opted to optimize diabetes management and reduce hepatic metabolic overload. Further investigations were conducted to rule out differential diagnoses, especially viral and autoimmune hepatitis. Poor acceptance of type 1 diabetes leads to non-compliance with insulin therapy. Then, energy metabolism becomes defective with growth retardation and pubertal delay. Glucose accumulates in the liver leading to metabolic liver disease. Liver damage could be irreversible. Therapeutic education, a good doctor-patient relationship, and family support are the cornerstones of managing T1DM diabetes complicated by Mauriac syndrome.

Glycogen homeostasis and mtDNA expression require motor neuron to muscle TGFβ/Activin Signaling in Drosophila

Maintaining metabolic homeostasis requires coordinated nutrient utilization between intracellular organelles and across multiple organ systems. Many organs rely heavily on mitochondria to generate (ATP) from glucose, or stored glycogen. Proteins required for ATP generation are encoded in both nuclear and mitochondrial DNA (mtDNA). We show that motoneuron to muscle signaling by the TGFβ/Activin family member Actβ positively regulates glycogen levels during Drosophila development. Remarkably, we find that levels of stored glycogen are unaffected by altering cytoplasmic glucose catabolism. Instead, Actβ loss reduces levels of mtDNA and nuclearly encoded genes required for mtDNA replication, transcription and translation. Direct RNAi mediated knockdown of these same nuclearly encoded mtDNA expression factors also results in decreased glycogen stores. Lastly, we find that expressing an activated form of the type I receptor Baboon in muscle restores both glycogen and mtDNA levels in actβ mutants, thereby confirming a direct link between Actβ signaling, glycogen homeostasis and mtDNA expression.

Evaluating the effectiveness of a novel somatostatin receptor 2 antagonist, ZT-01, for hypoglycemia prevention in a rodent model of type 2 diabetes

Background: Elevated levels of somatostatin blunt glucagon counterregulation during hypoglycemia in type 1 diabetes (T1D) and this can be improved using somatostatin receptor 2 (SSTR2) antagonists. Hypoglycemia also occurs in late-stage type 2 diabetes (T2D), particularly when insulin therapy is initiated, but the utility of SSTR2 antagonists in ameliorating hypoglycemia in this disease state is unknown. We examined the efficacy of a single-dose of SSTR2 antagonists in a rodent model of T2D. Methods: High-fat fed (HFF), low dose streptozotocin (STZ, 35 mg/kg)-induced T2D and HFF only, nondiabetic (controls-no STZ) rats were treated with the SSTR2 antagonists ZT-01/PRL-2903 or vehicle (n = 9-11/group) 60 min before an insulin tolerance test (ITT; 2-12 U/kg insulin aspart) or an oral glucose tolerance test (OGTT; 2 g/kg glucose via oral gavage) on separate days. Results: This rodent model of T2D is characterized by higher baseline glucose and HbA1c levels relative to HFF controls. T2D rats also had lower c-peptide levels at baseline and a blunted glucagon counterregulatory response to hypoglycemia when subjected to the ITT. SSTR2 antagonists increased the glucagon response and reduced incidence of hypoglycemia, which was more pronounced with ZT-01 than PRL-2903. ZT-01 treatment in the T2D rats increased glucagon levels above the control response within 60 min of dosing, and values remained elevated during the ITT (glucagon Cmax: 156 ± 50 vs. 77 ± 46 pg/mL, p < 0.01). Hypoglycemia incidence was attenuated with ZT-01 vs. controls (63% vs. 100%) and average time to hypoglycemia onset was also delayed (103.1 ± 24.6 vs. 66.1 ± 23.6 min, p < 0.05). ZT-01 administration at the OGTT onset increased the glucagon response without exacerbating hyperglycemia (2877 ± 806 vs. 2982 ± 781), potentially due to the corresponding increase in c-peptide levels (6251 ± 5463 vs. 14008 ± 5495, p = 0.013). Conclusion: Treatment with SSTR2 antagonists increases glucagon responses in a rat model of T2D and results in less hypoglycemia exposure. Future studies are required to determine the best dosing periods for chronic SSTR2 antagonism treatment in T2D.

Hepatic Glycogenosis: An Underdiagnosed Entity?

Hepatic glycogenosis (HG) is a rare complication of long-standing poorly controlled type 1 diabetes mellitus (T1DM), which is often misdiagnosed as non-alcoholic fatty liver disease (NAFLD). Despite the existence of several reports in the literature, it still is underrecognized, even among gastroenterologists. Differential diagnosis between these entities is essential since they have different prognoses.

We report a case of an 18-year-old female, with a medical history of poorly controlled T1DM, admitted to an intensive care unit with severe diabetic ketoacidosis (DKA). Upon admission, aminotransferases were significantly elevated; bilirubin and coagulation tests were normal. Despite adequate DKA treatment, she had persistently elevated aminotransferases and hyperlactacidemia. Imaging studies showed hepatomegaly and bright liver parenchyma. Extensive laboratory workup was negative for other causes of liver disease. So, a liver biopsy was performed, which was consistent with the diagnosis of HG. Under strict metabolic control, she had progressive improvement, achieving biochemical normalization within 6 months.

This case highlights the need for clinicians to be aware of this condition due to non-negligible differences between HG and NAFLD, with the latter progressing to fibrosis, and ultimately cirrhosis and hepatocarcinoma. On the opposite, HG is considered a benign condition, associated with an excellent prognosis that can be reversible after adequate metabolic control. Liver biopsy remains the gold standard method for HG diagnosis since it can distinguish it from NAFLD.

Beneficial effects of voluntary wheel running on activity rhythms, metabolic state, and affect in a diurnal model of circadian disruption

Emerging evidence suggests that disruption of circadian rhythmicity contributes to development of comorbid depression, cardiovascular diseases (CVD), and type 2 diabetes mellitus (T2DM). Physical exercise synchronizes the circadian system and has ameliorating effects on the depression- and anxiety-like phenotype induced by circadian disruption in mice and sand rats. We explored the beneficial effects of voluntary wheel running on daily rhythms, and the development of depression, T2DM, and CVD in a diurnal animal model, the fat sand rat (Psammomys obesus). Voluntary exercise strengthened general activity rhythms, improved memory and lowered anxiety- and depressive-like behaviors, enhanced oral glucose tolerance, and decreased plasma insulin levels and liver weight. Animals with access to a running wheel had larger heart weight and heart/body weight ratio, and thicker left ventricular wall. Our results demonstrate that exercising ameliorates pathological-like daily rhythms in activity and blood glucose levels, glucose tolerance and depressive- and anxiety-like behaviors in the sand rat model, supporting the important role of physical activity in modulating the “circadian syndrome” and circadian rhythm-related diseases. We suggest that the utilization of a diurnal rodent animal model may offer an effective way to further explore metabolic, cardiovascular, and affective-like behavioral changes related to chronodisruption and their underlying mechanisms.

Insulin overdose complicated by treatment‐induced acute hepatic steatosis in a nondiabetic patient

Background

There are few reports of dextrose‐associated hepatic steatosis during insulin overdose treatment. Reports in nondiabetic patients are extremely rare. There is inadequate knowledge about the clinical course and treatment.

Case Presentation

A 37‐year‐old previously healthy, nondiabetic man self‐administered 5,925 IU of insulin. On admission, his liver function tests were normal. However, following continued dextrose treatment, they increased, and he was diagnosed with hepatic steatosis. The liver function tests improved with decreasing dextrose dosage, and he was asymptomatic on discharge.

Conclusion

Acute hepatic steatosis may occur in nondiabetic and diabetic patients during treatment requiring large doses of dextrose infusion, such as for an insulin overdose. In addition, the degree of liver damage might also be related to the dextrose dose. Therefore, careful glycemic control and minimization of the dextrose dosage are recommended for diabetic and nondiabetic patients.

Liver chemistries in glycogenic hepatopathy associated with type 1 diabetes mellitus: A systematic review and pooled analysis

BACKGROUND & AIMS

Glycogenic hepatopathy (GH) in type 1 diabetes-mellitus (T1DM) is characterized by hepatomegaly and perturbations of liver chemistries (LC) that have not been well studied. Furthermore, misdiagnosis with other hepatic complications of T1DM, such as nonalcoholic fatty liver disease, has been described. We perform a systematic review of biopsy-proven GH reports in T1DM patients to identify LC patterns.

METHODS

A systematic review identified reports of biopsy-proven GH in patients with T1DM. We excluded GH with other liver diseases, Mauriac syndrome, or GH without T1DM. Two reviewers screened and extracted studies and assessed their methodological quality. LC elevation magnitude, AST-to-ALT ratio, R-ratio to designate hepatocellular, cholestatic or mixed pattern of hepatic injury, and evolution of transaminases after glycemic control were analyzed.

RESULTS

A total of 192 patients were included, with median age of 20 years, 73% adults, 66% females, median duration of T1DM before diagnosis 10 years, median adult body mass index 21 kg/m² , median HbA1c 12%, at least one episode of diabetic ketoacidosis 70%, and hepatomegaly 92%. ALT and AST showed moderate-to-severe elevation in 78% and 76%, respectively, AST/ALT >1 in 71% and hepatocellular to mixed pattern of hepatic injury in 81%. Transaminase improvement with glycemic control was the rule, regardless of other factors in multilinear regression analysis.

CONCLUSION

GH tends to have AST-predominant elevation with a median of 13 times the upper normal limit and R-ratio >2, which may distinguish it from other etiologies of AST-predominant LC elevation, and in the appropriate clinical context, may obviate invasive tests.

Hepatomegaly and short stature in a 14-year-old with type 1 diabetes mellitus: case report

BACKGROUND

Mauriac syndrome is a rare consequence of poorly controlled insulin-dependent diabetes, characterized by hepatomegaly, growth failure, delayed onset of puberty, and cushingoid features. Case reports of patients with Mauriac syndrome are found infrequently in the literature given historic improvements in diabetes management due to readily available insulin therapy.

METHODS

We describe a case of a 14-year-old girl who presented with acute onset abdominal pain, distention, and orthopnea.

RESULTS

She had a history of poorly controlled insulin-dependent diabetes as well as short stature. Abdominal imaging revealed impressive hepatomegaly. Laboratory testing showed markedly elevated triglycerides and cholesterol. Mauriac syndrome was suspected and diagnosed by liver biopsy, which demonstrated significant glycogenic hepatopathy.

CONCLUSIONS

This case provides an illustrative example of Mauriac syndrome in a child who did not experience delayed onset of puberty and continued to have regular menses unlike what has been previously described. Furthermore, this case highlights the important consideration for significant dyslipidemia in patients with Mauriac syndrome and discusses the challenges of controlling insulin-dependent diabetes in the adolescent population.

Image of the month: Mauriac variant: a rare complication of poorly controlled diabetes

We present a case of Mauriac syndrome in a young woman with poorly controlled type 1 diabetes mellitus. Liver complications are well known in the context of type 2 diabetes mellitus, it is associated metabolic complications and with the non-alcoholic fatty liver disease spectrum. This case brings to light a less well-known liver complication associated with type 1 diabetes mellitus.

Diabetic‑induced alterations in hepatic glucose and lipid metabolism: The role of type 1 and type 2 diabetes mellitus (Review)

Diabetes mellitus (DM) is a growing health concern in society. Type 1 and type 2 DM are the two main types of diabetes; both types are chronic diseases that affect glucose metabolism in the body and the impaired regulation of glucose and lipid metabolism promotes the development and progression of DM. During the physiological metabolism process, the liver serves a unique role in glucose and lipid metabolism. The present article aimed to review the association between DM and glucose metabolism in the liver and discuss the changes of the following hepatic glucose fluxes: Gluconeogenesis, glucose/glucose 6‑phosphate cycling, glycogenolysis, glycogenesis and the pentose phosphate pathway. Moreover, the incidence of fatty liver in DM was also investigated.

Hepatocellular Glycogen Accumulation in the Setting of Poorly Controlled Type 1 Diabetes Mellitus: Case Report and Review of the Literature

Glycogenic hepatopathy (GH) is the accumulation of glycogen in the hepatocytes and represents a rare complication in patients with diabetes mellitus (DM), most commonly type 1 DM. We present a case of a 23-year-old woman with a medical history of poorly controlled type 1 DM and gastroesophageal reflux disease (GERD) who presented with progressively worsening right-sided abdominal pain. Diagnostic workup resulted in a liver biopsy with hepatocytes that stained heavily for glycogen with no evidence of fibrosis or steatohepatitis. A diagnosis of glycogenic hepatopathy was made, and an aggressive glucose control regimen was implemented leading to resolution of symptoms and improvement in AST, ALT, and ALP. In addition to presenting this rare case, we offer a review of literature and draw important distinctions between glycogenic hepatopathy and other differential diagnoses with the aim of assisting providers in the diagnostic workup and treatment of glycogenic hepatopathy.

Olmesartan attenuates type 2 diabetes-associated liver injury: Cross-talk of AGE/RAGE/JNK, STAT3/SCOS3 and RAS signaling pathways

Olmesartan (OLM), an angiotensin receptor blocker, was tested against diabetes/insulin resistance (IR) models associated with renal/cardiovascular complications. Methods: we tested its potential role against diabetes-induced hepatic hitches using an IR/type2 diabetic (IR/D) model induced by high fat/high fructose diet for 7 weeks ​+ ​a single sub-diabetogenic dose of streptozotocin (35mg/kg; i.p). IR/D rats were orally treated with OLM (10 ​mg/kg), pioglitazone (PIO; 5 or 10 ​mg/kg) or their combinations for 4 consecutive weeks. OLM alone opposed the detrimental effects of IR/D; it significantly improved metabolic parameters, liver function, and abated hepatic oxidative stress, and inflammatory cytokine interleukin-6 (IL-6) and its upstream mediator nuclear factor kappa B. Consequently, OLM turned off the downstream cue p-Jak2/STAT3/SOCS3. Moreover, it suppressed the elevated AGE/RAGE/p-JNK pathway and increased the PPARγ/adiponectin cue to signify its anti-inflammatory and anti-oxidant capacity (GSH, MDA). Nevertheless, co-administration of OLM to PIO showed a synergistic improvement in all the aforementioned parameters in a dose dependent manner. Additionally, OLM with PIO₁₀ provoked a surge in hepatic PPARγ and adiponectin (5 and 6 folds) with a sharp decrease of about 85% in the NF-κB/IL-6/p-STAT3/SCOS3 pathway. These effects were confirmed by the histopathological study. In conclusion, OLM and its combination with PIO enhanced insulin sensitivity and guarded against hepatic complications associated with type 2 diabetes probably via modulating various inter-related pathways; namely, metabolic alteration, renin-angiotensin system, inflammatory trajectories, as well as oxidative stress. This study manifests the potential synergistic effects of OLM as an adjuvant therapy to the conventional antidiabetic therapies.

Mauriac Syndrome: A Rare Hepatic Glycogenosis in Poorly Controlled Type 1 Diabetes

Background

Hepatic glycogenosis (HG) is a complication of poorly controlled type 1 diabetes mellitus (T1DM), characterized by glycogen accumulation in hepatocytes. Mauriac syndrome (MS) is a glycogenic hepatopathy, initially described in 1930, characterized by growth failure, delayed puberty, cushingoid appearance, hepatomegaly with abnormal liver enzymes, and hypercholesterolemia. HG is a condition with good prognosis and fast resolution after adequate glycemic control (although it has potential for relapse), with no case of evolution to end-stage liver disease described.

Case

We describe a 26-year-old female, with T1DM complicated by severe retinopathy. The patient maintained poor glycemic control since childhood, presenting glycated hemoglobin persistently higher than 10% and recurrent episodes of ketoacidosis. In adolescence, she developed hepatomegaly and fluctuating elevation of aminotransferases and triglycerides. A small, nonrepresentative hepatic biopsy suggested macrovacuolar steatosis and mild fibrosis. After 15 years of diabetes, the patient was referred for gastroenterology clinic due to chronic diarrhea and exuberant hepatomegaly. Laboratory showed persistent elevation of aminotransferases and triglycerides. Bilirubin, iron metabolism, and coagulation were normal; viral serologies and autoimmune study were negative. Upper endoscopy, ileocolonoscopy, and enteroscopy presented no lesions. Abdominal magnetic resonance imaging displayed massive hepatomegaly. Liver biopsy was repeated showing marked nuclear glycogenization, mild steatosis, and no fibrosis; electron microscopy revealed very large deposits of glycogen and pleomorphic mitochondria with an unusually dense matrix, described for the first time in this entity. The diagnosis of MS variant and diarrhea due to autonomic neuropathy were assumed.

Conclusion

Currently, HG is a well-recognized disease that occurs at any age and can be present without the full spectrum of features initially described for MS. In the era of insulin therapy, this entity represents a rare complication, caused by low therapeutic compliance.

Glycogenic hepatopathy as a cause of severe deranged liver enzymes in a young patient with type 1 diabetes mellitus

Glycogenic hepatopathy (GH) is a rare complication of poorly controlled type 1 diabetes mellitus (T1DM). We present a 19-year-old woman with T1DM and autoimmune thyroiditis who admitted to our department because of abrupt onset intermittent abdominal pain in the right upper quadrant accompanied by laboratory evidence of acute anicteric hepatitis. Physical examination revealed significant hepatomegaly but the common imagining studies were negative. Following exclusion of common causes of acute hepatitis and because of the presence of smooth muscle antibodies in a young female patient with already established two autoimmune diseases, a liver biopsy was performed in order to exclude the potential presence of autoimmune hepatitis. However, liver histology showed typical findings of GH. Intense treatment targeting strict glycemic control resulted in normalisation of liver biochemistry. This case underlines that GH should be considered as a rare cause of acute hepatitis in T1DM patients with poor glycemic control.

Mauriac Syndrome: A Rare Complication of Type 1 Diabetes Mellitus

Mauriac syndrome, first described in 1930, is typically diagnosed in young patients with poorly controlled type 1 diabetes mellitus and growth retardation, delayed puberty, Cushingoid features, hypercholesterolaemia and hepatomegaly. However, the sole presenting feature of Mauriac syndrome can be hepatic glycogenosis in both adults and children. The mainstay of treatment for hepatic glycogenosis is strict control of glucose levels, with an excellent prognosis with improved glycaemic control. The authors present the case of a 22-year-old female patient with type 1 diabetes mellitus and a history of poor glycaemic control who was admitted with diabetic ketoacidosis (DKA). She complained of episodes of right upper quadrant abdominal pain associated with nausea and vomiting for the last 2 months with worsening in the last 48 hours. Physical examination was remarkable for short stature and tenderness over the hepatic area with a mildly enlarged liver. The patient had elevated liver enzymes and persistent hyperlactacidaemia despite DKA resolution. Liver imaging suggested diffuse fat infiltration. The clinical suspicion of hepatic glycogenosis was confirmed by liver biopsy. After glycaemic control was improved, liver enzymes normalized and the episodes of abdominal pain, nausea and vomiting subsided.

LEARNING POINTS

Hepatic glycogenosis can be the sole presenting feature of Mauriac syndrome.Hepatic glycogenosis is an under-recognized cause of abdominal pain in patients with type 1 diabetes mellitus.Hepatic glycogenosis may be confused with non-alcoholic fatty liver disease, with important therapeutic implications and a distinct prognosis.The mainstay of treatment for hepatic glycogenosis is strict glycaemic control with an excellent prognosis when achieved.

Hepatomegaly and type 1 diabetes: a clinical case of Mauriac's syndrome

Background

Hepatic glycogenosis is characterized by excessive glycogen accumulation in hepatocytes and represents a complication of poor controlled type 1 diabetes. It can be caused by excessive insulin doses or recurrent ketoacidosis episodes. Mauriac’s syndrome is a rare disease, which includes short stature, growth maturation delay, dyslipidemia, moon facies, protuberant abdomen, hepatomegaly with transaminase elevation. It has become even less common after the emergence of advances on diabetes treatment, but still exists. Recent reports described glycogenosis without the full spectrum of Mauriac’s syndrome in both adults and children with brittle diabetes. Clinical, laboratory and histological abnormalities are reversible with appropriate glycemic control.

Case presentation

We hereby report a case of 11-year-old male who presented with hepatic glycogenosis mimicking Mauriac’s syndrome. The patient was admitted at our Pediatric Diabetes Clinic for marked hepatomegaly, short stature and for the poor metabolic control. Blood investigations and liver tests excluded most of major causes of hepatopathy. A liver biopsy allowed us to make diagnosis of hepatic glycogenosis. To control hyperglycaemia, initially we titrated daily insulin dosage, and then intravenous insulin treatment was practiced with the consequent normalization of liver enzymes.

Conclusion

Mauriac’s syndrome should be considered in subjects with brittle type 1 diabetes and hepatomegaly.

Potential activities and mechanisms of extracellular polysaccharopeptides from fermented Trametes versicolor on regulating glucose homeostasis in insulin-resistant HepG2 cells

Polysaccharides derived from mushrooms have potential to control blood sugar, reduce insulin resistance and prevent diabetic complications. The intracellular polysaccharopeptides of Trametes versicolor (TV) have been used as immunologic and oncologic adjuvants. The aim of this study was to investigate the potential activities and mechanisms of extracellular polysaccharopeptides (ePSP) obtained from TV strain LH-1 on regulating glucose homeostasis. Human hepatoma HepG2 cells incubated with normal glucose (5.5 mM, NG model), high glucose (33 mM, HG model), or high glucose (33 mM) plus high insulin (10⁻⁷ M, HGI model) concentrations were administered with TV LH-1 ePSP (50, 100, and 1000 μg/ml) for 24 hr. Glucose uptake of HepG2 cells, determined by flow cytometry, was significantly decreased in the HG and HGI models with insulin stimulation, suggesting insulin resistance of these cells; however, ePSP reversed this decrease in a dose-dependent manner (one-way ANOVA, p<0.05). In the HG and HGI models, ePSP significantly increased glycogen content, insulin receptor substrate-2 protein and phosphorylated AMP-activated protein kinase (AMPK), as determined by western blot analysis. In addition, ePSP significantly increased glucokinase in the NG and HG models, increased membrane glucose transporter-1 and decreased glycogen synthase kinase-3β in the HGI model, and increased glucose-6-phosphatase in the NG and HGI models (one-way ANOVA, p<0.05). In summary, TV LH-1 ePSP may elevate cellular glucose uptake to regulate glucose homeostasis via the activation of AMPK and glycogen synthesis in an insulin-independent manner. These results suggest that TV LH-1 ePSP may be a nutraceutical with anti-hyperglycemic activity.

Glycogen Hepatopathy: A Rare and Underrecognized Cause of Recurrent Transaminitis in Patients with Uncontrolled Type 2 Diabetes Mellitus

Glycogen hepatopathy (GH), characterized by reversible transaminitis and hepatomegaly, results from excessive accumulation of glycogen in hepatocytes. GH has been well described in the literature as a rare cause of transaminitis in children and young patients with uncontrolled type 1 diabetes mellitus and has rarely been reported in type 2 diabetic patients. Hyperglycemia and hyperinsulinemia are believed to be a metabolic substrate for hepatic glycogen accumulation and in order to cause glycogen hepatotoxicity. We present the case of a 54-year-old woman with poorly controlled insulin-dependent type 2 diabetes who was hospitalized twice within 1 month with diabetic ketoacidosis/hyperosmolar hyperglycemic state and reversible transaminitis. Interestingly, she had normal liver function tests performed at the time of admission and transaminitis was noted 1 day later, after she was treated with high doses of intravenous insulin therapy. Subsequently, liver enzymes recovered to normal levels with optimization of glucose control.

Clear cell hepatocellular carcinoma: origin, metabolic traits and fate of glycogenotic clear and ground glass cells

Clear cell hepatocellular carcinoma (CCHCC) has hitherto been considered an uncommon, highly differentiated variant of hepatocellular carcinoma (HCC) with a relatively favorable prognosis. CCHCC is composed of mixtures of clear and/or acidophilic ground glass hepatocytes with excessive glycogen and/or fat and shares histology, clinical features and etiology with common HCCs. Studies in animal models of chemical, hormonal and viral hepatocarcinogenesis and observations in patients with chronic liver diseases prone to develop HCC have shown that the majority of HCCs are preceded by, or associated with, focal or diffuse excessive storage of glycogen (glycogenosis) which later may be replaced by fat (lipidosis/steatosis). In ground glass cells, the glycogenosis is accompanied by proliferation of the smooth endoplasmic reticulum, which is closely related to glycogen particles and frequently harbors the hepatitis B surface antigen (HBsAg). From the findings in animal models a sequence of changes has been established, commencing with preneoplastic glycogenotic liver lesions, often containing ground glass cells, and progressing to glycogen-poor neoplasms via various intermediate stages, including glycogenotic/lipidotic clear cell foci, clear cell hepatocellular adenomas (CCHCA) rich in glycogen and/or fat, and CCHCC. A similar process seems to take place in humans, with clear cells frequently persisting in CCHCC and steatohepatitic HCC, which presumably represent intermediate stages in the development rather than particular variants of HCC. During the progression of the preneoplastic lesions, the clear and ground glass cells transform into cells characteristic of common HCC. The sequential cellular changes are associated with metabolic aberrations, which start with an activation of the insulin signaling cascade resulting in pre-neoplastic hepatic glycogenosis. The molecular and metabolic changes underlying the glycogenosis/lipidosis are apparently responsible for the dramatic metabolic shift from gluconeogenesis to the pentose phosphate pathway and Warburg-type glycolysis, which provide precursors and energy for an ever increasing cell proliferation during progression.

Glycogenic hepatopathy in young adults: a case series

Glycogenic hepatopathy is a rare and under-recognized complication in long-standing poorly controlled type 1 diabetes mellitus patients. This is a distinct entity from other causes of hepatomegaly and elevated liver enzymes in diabetics, such as nonalcoholic fatty liver disease. Glycogenic hepatopathy is characterized by the combination of poorly controlled diabetes, acute liver injury with marked elevation in serum aminotransferases, and the characteristic histological features on liver biopsy. It is important to distinguish this entity as it has the potential for resolution following improved glycemic control. In this report, we describe four cases of adult patients presenting elevated serum transaminases and hepatomegaly with a history of poorly controlled type I diabetes mellitus. One of the patients had also elevated amylase and lipase in the serum, without clinical or imagiologic evidence of acute pancreatitis (AP). Liver biopsy was performed in all patients and revealed glycogenic hepatopathy. Clinician's awareness of glycogenic hepatopathy should prevent diagnostic delay or misdiagnosis and will provide better insight and management for this condition.

Focal Hepatic Glycogenosis in a Patient With Uncontrolled Diabetes Mellitus Type 1

Hepatomegaly and elevated liver enzymes in patients with diabetes are commonly associated with fatty liver disease. However, physicians often forget about another intrinsic substance that can cause a similar clinical picture-glycogen. Liver stores approximately one third of the total body glycogen and is responsible for blood glucose homeostasis. Excessive hepatocellular glycogen accumulation occurs not only in congenital glycogen storage diseases, but also in acquired conditions associated with hyperglycemic-hyperinsulinemic states such as uncontrolled diabetes mellitus, high-dose corticosteroid use, and dumping syndrome. All reported cases of acquired abnormal glycogen deposition described a diffuse form of hepatic glycogenosis with the entire liver involved in the accumulating process. To our knowledge, this is the first reported case of abnormal focal glycogen deposition in a patient with diabetes mellitus type 1 with imaging and pathologic correlation. Awareness of the imaging appearance of focal glycogen deposition can help to distinguish it from other pathologic conditions.

Hepatic Overexpression of CD36 Improves Glycogen Homeostasis and Attenuates High-Fat Diet-Induced Hepatic Steatosis and Insulin Resistance

The common complications in obesity and type 2 diabetes include hepatic steatosis and disruption of glucose-glycogen homeostasis, leading to hyperglycemia. Fatty acid translocase (FAT/CD36), whose expression is inducible in obesity, is known for its function in fatty acid uptake. Previous work by us and others suggested that CD36 plays an important role in hepatic lipid homeostasis, but the results have been conflicting and the mechanisms were not well understood. In this study, by using CD36-overexpressing transgenic (CD36Tg) mice, we uncovered a surprising function of CD36 in regulating glycogen homeostasis. Overexpression of CD36 promoted glycogen synthesis, and as a result, CD36Tg mice were protected from fasting hypoglycemia. When challenged with a high-fat diet (HFD), CD36Tg mice showed unexpected attenuation of hepatic steatosis, increased very low-density lipoprotein (VLDL) secretion, and improved glucose tolerance and insulin sensitivity. The HFD-fed CD36Tg mice also showed decreased levels of proinflammatory hepatic prostaglandins and 20-hydroxyeicosatetraenoic acid (20-HETE), a potent vasoconstrictive and proinflammatory arachidonic acid metabolite. We propose that CD36 functions as a protective metabolic sensor in the liver under lipid overload and metabolic stress. CD36 may be explored as a valuable therapeutic target for the management of metabolic syndrome.

Hyperketonemia and ketosis increase the risk of complications in type 1 diabetes

Diets that boost ketone production are increasingly used for treating several neurological disorders. Elevation in ketones in most cases is considered favorable, as they provide energy and are efficient in fueling the body's energy needs. Despite all the benefits from ketones, the above normal elevation in the concentration of ketones in the circulation tend to illicit various pathological complications by activating injurious pathways leading to cellular damage. Recent literature demonstrates a plausible link between elevated levels of circulating ketones and oxidative stress, linking hyperketonemia to innumerable morbid conditions. Ketone bodies are produced by the oxidation of fatty acids in the liver as a source of alternative energy that generally occurs in glucose limiting conditions. Regulation of ketogenesis and ketolysis plays an important role in dictating ketone concentrations in the blood. Hyperketonemia is a condition with elevated blood levels of acetoacetate, 3-β-hydroxybutyrate, and acetone. Several physiological and pathological triggers, such as fasting, ketogenic diet, and diabetes cause an accumulation and elevation of circulating ketones. Complications of the brain, kidney, liver, and microvasculature were found to be elevated in diabetic patients who had elevated ketones compared to those diabetics with normal ketone levels. This review summarizes the mechanisms by which hyperketonemia and ketoacidosis cause an increase in redox imbalance and thereby increase the risk of morbidity and mortality in patients.

Role of stem cells during diabetic liver injury

Diabetes mellitus is one of the most severe endocrine metabolic disorders in the world that has serious medical consequences with substantial impacts on the quality of life. Type 2 diabetes is one of the main causes of diabetic liver diseases with the most common being non-alcoholic fatty liver disease. Several factors that may explain the mechanisms related to pathological and functional changes of diabetic liver injury include: insulin resistance, oxidative stress and endoplasmic reticulum stress. The realization that these factors are important in hepatocyte damage and lack of donor livers has led to studies concentrating on the role of stem cells (SCs) in the prevention and treatment of liver injury. Possible avenues that the application of SCs may improve liver injury include but are not limited to: the ability to differentiate into pancreatic β-cells (insulin producing cells), the contribution for hepatocyte regeneration, regulation of lipogenesis, glucogenesis and anti-inflammatory actions. Once further studies are performed to explore the underlying protective mechanisms of SCs and the advantages and disadvantages of its application, there will be a greater understand of the mechanism and therapeutic potential. In this review, we summarize the findings regarding the role of SCs in diabetic liver diseases.