Currently,scientific interest has focused on fat accumulation outside of subcutaneous adipose tissue.As various imaging modalities are available to quantify fat accumulation in partic-ular organs,fatty pancreas has be...Currently,scientific interest has focused on fat accumulation outside of subcutaneous adipose tissue.As various imaging modalities are available to quantify fat accumulation in partic-ular organs,fatty pancreas has become an important area of research over the last decade.The pancreas has an essential role in regulating glucose metabolism and insulin secretion by responding to changes in nutrients under various metabolic circumstances.Mounting evidence has revealed that fatty pancreas is linked to impairedβ-cell function and affects in-sulin secretion with metabolic consequences of impaired glu-cose metabolism,type 2 diabetes,and metabolic syndrome.It has been shown that there is a connection between fatty pancreas and the presence and severity of nonalcoholic fatty liver disease(NAFLD),which has become the predominant cause of chronic liver disease worldwide.Therefore,it is nec-essary to better understand the pathogenic mechanisms of fat accumulation in the pancreas and its relationship with NAFLD.This review summarizes the epidemiology,diagnosis,risk factors,and metabolic consequences of fatty pancreas and discusses its pathophysiology links to NAFLD.展开更多
The pancreaticβ-cell failure which invariably accompanies insulin resistance in the liver and skeletal muscle is a hallmark of type-2 diabetes mellitus(T2DM).The persistent hyperglycemia of T2DM is often treated with...The pancreaticβ-cell failure which invariably accompanies insulin resistance in the liver and skeletal muscle is a hallmark of type-2 diabetes mellitus(T2DM).The persistent hyperglycemia of T2DM is often treated with anti-diabetic drugs with or without subcutaneous insulin injections,neither of which mimic the physiological glycemic control seen in individuals with fully functional pancreas.A sought after goal for the treatment of T2DM has been to harness the regenerative potential of pancreaticβ-cells that might obviate a need for exogenous insulin injections.A new study towards attaining this aim was reported by Yi et al,who have characterized a liver-derived protein,named betatrophin,capable of inducing pancreaticβ-cell proliferation in mice.Using a variety of in vitro and in vivo methods,Yi et al,have shown that betatrophin was expressed mainly in the liver and adipose tissue of mice.Exogenous expression of betatrophin in the liver led to dramatic increase in the pancreaticβ-cell mass and higher output of insulin in mice that also concomitantly elicited improved glucose tolerance.The authors discovered that betatrophin was also present in the human plasma.Surprisingly,betatrophin has been previously described by three other names,i.e.,re-feeding-induced fat and liver protein,lipasin and atypical angiopoeitin-like 8,by three independent laboratories,as nutritionally regulated liver-enriched factors that control serum triglyceride levels and lipid metabolism.Yi et al demonstration of betatrophin,as a circulating hormone that regulatesβ-cell proliferation,if successfully translated in the clinic,holds the potential to change the course of current therapies for diabetes.展开更多
The pancreas became one of the first objects of regenerative medicine,since other possibilities of dealing with the pancreatic endocrine insufficiency were clearly exhausted.The number of people living with diabetes m...The pancreas became one of the first objects of regenerative medicine,since other possibilities of dealing with the pancreatic endocrine insufficiency were clearly exhausted.The number of people living with diabetes mellitus is currently approaching half a billion,hence the crucial relevance of new methods to stimulate regeneration of the insulin-secretingβ-cells of the islets of Langerhans.Natural restrictions on the islet regeneration are very tight;nevertheless,the islets are capable of physiological regeneration viaβ-cell self-replication,direct differentiation of multipotent progenitor cells and spontaneousα-toβ-orδ-toβ-cell conversion(trans-differentiation).The existing preclinical models ofβ-cell dysfunction or ablation(induced surgically,chemically or genetically)have significantly expanded our understanding of reparative regeneration of the islets and possible ways of its stimulation.The ultimate goal,sufficient level of functional activity ofβ-cells or their substitutes can be achieved by two prospective broad strategies:β-cell replacement andβ-cell regeneration.The“regeneration”strategy aims to maintain a preserved population ofβ-cells through in situ exposure to biologically active substances that improveβ-cell survival,replication and insulin secretion,or to evoke the intrinsic adaptive mechanisms triggering the spontaneous non-β-toβ-cell conversion.The“replacement”strategy implies transplantation ofβ-cells(as non-disintegrated pancreatic material or isolated donor islets)orβ-like cells obtained ex vivo from progenitors or mature somatic cells(for example,hepatocytes orα-cells)under the action of small-molecule inducers or by genetic modification.We believe that the huge volume of experimental and clinical studies will finally allow a safe and effective solution to a seemingly simple goal-restoration of the functionally activeβ-cells,the innermost hope of millions of people globally.展开更多
Type 2 diabetes mellitus(T2DM)therapy is facing the challenges of long-term medication and gradual destruction of pancreatic isletβ-cells.Therefore,it is timely to develop oral prolonged action formulations to improv...Type 2 diabetes mellitus(T2DM)therapy is facing the challenges of long-term medication and gradual destruction of pancreatic isletβ-cells.Therefore,it is timely to develop oral prolonged action formulations to improve compliance,while restoringβ-cells survival and function.Herein,we designed a simple nanoparticle with enhanced oral absorption and pancreas accumulation property,which combined apical sodiumdependent bile acid transporter-mediated intestinal uptake and lymphatic transportation.In this system,taurocholic acid(TCA)modified poly(lactic-co-glycolic acid)(PLGA)was employed to achieve pancreas location,hydroxychloroquine(HCQ)was loaded to execute therapeutic efficacy,and 1,2-dilauroyl-sn-glycero-3-phosphocholine(DLPC)was introduced as stabilizer together with synergist(PLGA-TCA/DLPC/HCQ).In vitro and in vivo results have proven that PLGA-TCA/DLPC/HCQ reversed the pancreatic islets damage and dysfunction,thus impeding hyperglycemia progression and restoring systemic glucose homeostasis via only once administration every day.In terms of mechanism PLGA-TCA/DLPC/HCQ ameliorated oxidative stress,remodeled the inflammatory pancreas microenvironment,and activated PI3K/AKT signaling pathway without obvious toxicity.This strategy not only provides an oral delivery platform for increasing absorption and pancreas targetability but also opens a new avenue for thorough T2DM treatment.展开更多
Human induced pluripotent stem (hiPS) cells are considered a potential source for the generation of insulin-producing pancreatic β-ceUs because of their differentiation capacity. In this study, we have developed a ...Human induced pluripotent stem (hiPS) cells are considered a potential source for the generation of insulin-producing pancreatic β-ceUs because of their differentiation capacity. In this study, we have developed a five-step xeno-free culture system to efficiently dif- ferentiate hiPS cells into insulin-producing cells in vitro. We found that a high NOGGIN concentration is crucial for specifically inducing the differentiation first into pancreatic and duodenal homeobox-1 (PDX1)-positive pancreatic progenitors and then into neurogenin 3 (NGN3)-expressing pancreatic endocrine progenitors, while suppressing the differentiation into hepatic or intestinal cells. We also found that a combination of 3-isobutyl-l-methylxanthine (IBMX), exendin-4, and nicotinamide was important for the differentiation into insulin single-positive cells that expressed various pancreatic β-cell markers. Most notably, the differentiated cells contained en- dogenous C-peptide pools that were released in response to various insulin secretagogues and high levels of glucose. Therefore, our results demonstrate the feasibility of generating hiPS-derived pancreatic β-ceUs under xeno-free conditions and highlight their poten- tial to treat patients with type I diabetes.展开更多
文摘Currently,scientific interest has focused on fat accumulation outside of subcutaneous adipose tissue.As various imaging modalities are available to quantify fat accumulation in partic-ular organs,fatty pancreas has become an important area of research over the last decade.The pancreas has an essential role in regulating glucose metabolism and insulin secretion by responding to changes in nutrients under various metabolic circumstances.Mounting evidence has revealed that fatty pancreas is linked to impairedβ-cell function and affects in-sulin secretion with metabolic consequences of impaired glu-cose metabolism,type 2 diabetes,and metabolic syndrome.It has been shown that there is a connection between fatty pancreas and the presence and severity of nonalcoholic fatty liver disease(NAFLD),which has become the predominant cause of chronic liver disease worldwide.Therefore,it is nec-essary to better understand the pathogenic mechanisms of fat accumulation in the pancreas and its relationship with NAFLD.This review summarizes the epidemiology,diagnosis,risk factors,and metabolic consequences of fatty pancreas and discusses its pathophysiology links to NAFLD.
文摘The pancreaticβ-cell failure which invariably accompanies insulin resistance in the liver and skeletal muscle is a hallmark of type-2 diabetes mellitus(T2DM).The persistent hyperglycemia of T2DM is often treated with anti-diabetic drugs with or without subcutaneous insulin injections,neither of which mimic the physiological glycemic control seen in individuals with fully functional pancreas.A sought after goal for the treatment of T2DM has been to harness the regenerative potential of pancreaticβ-cells that might obviate a need for exogenous insulin injections.A new study towards attaining this aim was reported by Yi et al,who have characterized a liver-derived protein,named betatrophin,capable of inducing pancreaticβ-cell proliferation in mice.Using a variety of in vitro and in vivo methods,Yi et al,have shown that betatrophin was expressed mainly in the liver and adipose tissue of mice.Exogenous expression of betatrophin in the liver led to dramatic increase in the pancreaticβ-cell mass and higher output of insulin in mice that also concomitantly elicited improved glucose tolerance.The authors discovered that betatrophin was also present in the human plasma.Surprisingly,betatrophin has been previously described by three other names,i.e.,re-feeding-induced fat and liver protein,lipasin and atypical angiopoeitin-like 8,by three independent laboratories,as nutritionally regulated liver-enriched factors that control serum triglyceride levels and lipid metabolism.Yi et al demonstration of betatrophin,as a circulating hormone that regulatesβ-cell proliferation,if successfully translated in the clinic,holds the potential to change the course of current therapies for diabetes.
基金Supported by the President Grant for Government Support of Young Russian Scientists,No.075-15-2019-1120.
文摘The pancreas became one of the first objects of regenerative medicine,since other possibilities of dealing with the pancreatic endocrine insufficiency were clearly exhausted.The number of people living with diabetes mellitus is currently approaching half a billion,hence the crucial relevance of new methods to stimulate regeneration of the insulin-secretingβ-cells of the islets of Langerhans.Natural restrictions on the islet regeneration are very tight;nevertheless,the islets are capable of physiological regeneration viaβ-cell self-replication,direct differentiation of multipotent progenitor cells and spontaneousα-toβ-orδ-toβ-cell conversion(trans-differentiation).The existing preclinical models ofβ-cell dysfunction or ablation(induced surgically,chemically or genetically)have significantly expanded our understanding of reparative regeneration of the islets and possible ways of its stimulation.The ultimate goal,sufficient level of functional activity ofβ-cells or their substitutes can be achieved by two prospective broad strategies:β-cell replacement andβ-cell regeneration.The“regeneration”strategy aims to maintain a preserved population ofβ-cells through in situ exposure to biologically active substances that improveβ-cell survival,replication and insulin secretion,or to evoke the intrinsic adaptive mechanisms triggering the spontaneous non-β-toβ-cell conversion.The“replacement”strategy implies transplantation ofβ-cells(as non-disintegrated pancreatic material or isolated donor islets)orβ-like cells obtained ex vivo from progenitors or mature somatic cells(for example,hepatocytes orα-cells)under the action of small-molecule inducers or by genetic modification.We believe that the huge volume of experimental and clinical studies will finally allow a safe and effective solution to a seemingly simple goal-restoration of the functionally activeβ-cells,the innermost hope of millions of people globally.
基金supported by National Natural Science Foundation of China(Nos.81972893,and 82172719)Excellent Youth Science Foundation of Henan province(212300410071,China)Training program for young key teachers in Henan Province(2020GGJS019,China)。
文摘Type 2 diabetes mellitus(T2DM)therapy is facing the challenges of long-term medication and gradual destruction of pancreatic isletβ-cells.Therefore,it is timely to develop oral prolonged action formulations to improve compliance,while restoringβ-cells survival and function.Herein,we designed a simple nanoparticle with enhanced oral absorption and pancreas accumulation property,which combined apical sodiumdependent bile acid transporter-mediated intestinal uptake and lymphatic transportation.In this system,taurocholic acid(TCA)modified poly(lactic-co-glycolic acid)(PLGA)was employed to achieve pancreas location,hydroxychloroquine(HCQ)was loaded to execute therapeutic efficacy,and 1,2-dilauroyl-sn-glycero-3-phosphocholine(DLPC)was introduced as stabilizer together with synergist(PLGA-TCA/DLPC/HCQ).In vitro and in vivo results have proven that PLGA-TCA/DLPC/HCQ reversed the pancreatic islets damage and dysfunction,thus impeding hyperglycemia progression and restoring systemic glucose homeostasis via only once administration every day.In terms of mechanism PLGA-TCA/DLPC/HCQ ameliorated oxidative stress,remodeled the inflammatory pancreas microenvironment,and activated PI3K/AKT signaling pathway without obvious toxicity.This strategy not only provides an oral delivery platform for increasing absorption and pancreas targetability but also opens a new avenue for thorough T2DM treatment.
文摘Human induced pluripotent stem (hiPS) cells are considered a potential source for the generation of insulin-producing pancreatic β-ceUs because of their differentiation capacity. In this study, we have developed a five-step xeno-free culture system to efficiently dif- ferentiate hiPS cells into insulin-producing cells in vitro. We found that a high NOGGIN concentration is crucial for specifically inducing the differentiation first into pancreatic and duodenal homeobox-1 (PDX1)-positive pancreatic progenitors and then into neurogenin 3 (NGN3)-expressing pancreatic endocrine progenitors, while suppressing the differentiation into hepatic or intestinal cells. We also found that a combination of 3-isobutyl-l-methylxanthine (IBMX), exendin-4, and nicotinamide was important for the differentiation into insulin single-positive cells that expressed various pancreatic β-cell markers. Most notably, the differentiated cells contained en- dogenous C-peptide pools that were released in response to various insulin secretagogues and high levels of glucose. Therefore, our results demonstrate the feasibility of generating hiPS-derived pancreatic β-ceUs under xeno-free conditions and highlight their poten- tial to treat patients with type I diabetes.