The Investigation and Treatment of Diabetic Gastroparesis. Clin Ther. 2018;40:850-861. [PMID: 29748143 DOI: 10.1016/j.clinthera.2018.04.012]

Pathogenesis and management of diabetic gastroparesis: An updated clinically oriented review

BACKGROUND AND AIMS

Diabetic gastroparesis (DGp) is a common and preventable complication of uncontrolled diabetes mellitus (D.M.) and significantly affects the Quality of Life of patients. Diagnosis and management present as a clinical challenge due to the disease's complexity and limited effective therapeutic options. This review aims to comprehensively outline the pathogenesis, diagnosis, and management of diabetic gastroparesis, evaluating evolving approaches to guide clinicians and provide future recommendations.

METHODS

A literature review was conducted on scholarly databases of PubMed, Google Scholar, Scopus and Web of Science encompassing published articles, gray literature and relevant clinical guidelines. Data were synthesized and analyzed to provide a comprehensive overview of diabetic gastroparesis, focusing on pathogenesis, diagnosis, and management.

RESULTS

The review intricately explores the pathogenesis contributing to diabetic gastroparesis, emphasizing autonomic neuropathy, oxidative stress, inflammation, hormonal dysregulation, microbiota alterations, and gastrointestinal neuropathy. Primary management strategies are underscored, including lifestyle modifications, symptom relief, and glycemic control. The discussion encompasses pharmacological and surgical options, highlighting the importance of a multidisciplinary approach involving various healthcare professionals for comprehensive patient care.

CONCLUSION

This review offers a thorough understanding of pathogenesis, diagnosis, and management of diabetic gastroparesis, underlining evolving approaches for clinicians. A multidisciplinary approach is crucial to address both the physical and mental health aspects of diabetes and its complications.

17β-Estradiol Suppresses Gastric Inflammatory and Apoptotic Stress Responses and Restores nNOS-Mediated Gastric Emptying in Streptozotocin (STZ)-Induced Diabetic Female Mice

Gastroparesis (Gp) is a severe complication of diabetes mellitus (DM) observed predominantly in women. It is characterized by abnormal gastric emptying (GE) without mechanical obstruction in the stomach. Nitric oxide (NO) is an inhibitory neurotransmitter produced by neuronal nitric oxide synthase (nNOS). It plays a critical role in gastrointestinal (GI) motility and stomach emptying. Here, we wanted to demonstrate the protective effects of supplemental 17β-estradiol (E2) on NO-mediated gastric function. We showed E2 supplementation to alleviate oxidative and inflammatory stress in streptozotocin (STZ)-induced diabetic female mice. Our findings suggest that daily administration of E2 at therapeutic doses is beneficial for metabolic homeostasis. This restoration occurs via regulating and modulating the expression/function of glycogen synthase kinase-3β (GSK-3β), nuclear factor-erythroid 2 p45-related factor 2 (Nrf2), Phase II enzymes, MAPK- and nuclear factor kappa-light-chain-enhancer of activated B cells (NFkB)-mediated inflammatory cytokines (IL-1β, IL-6, TNFα, IGF-1), and gastric apoptotic regulators. We also showed E2 supplementation to elevate GCH-1 protein levels in female diabetic mice. Since GCH-1 facilitates the production of tetrahydrobiopterin (BH4, cofactor for nNOS), an increase in GCH-1 protein levels in diabetic mice may improve their GE and nitrergic function. Our findings provide new insights into the impact of estrogen on gastric oxidative stress and intracellular inflammatory cascades in the context of Gp.

Gastroparesis-Related Symptoms in Patients With Type 2 Diabetes Mellitus: Early Detection, Risk Factors, and Prevalence

Background The symptoms of gastroparesis, such as bloating, postprandial fullness, early satiety, nausea, and abdominal discomfort, progressively worsen the quality of life of the affected individuals. The diagnosis is established on the assessment of gastric function that confirms delayed gastric emptying in the absence of structural etiologies. This study aimed to detect gastroparesis-related clinical symptoms early in patients with type 2 diabetes mellitus (T2DM), investigate the concomitant risk factors, and evaluate the prevalence. Methodology This study was conducted at the Department of Medicine and Diabetes Outdoor Clinic of Sheikh Zayed Hospital, Rahim Yar Khan from February 13, 2022, to February 11, 2023. The study involved 175 patients with T2DM who reported gastroparesis-related symptoms. The demographic and clinical characteristics, symptom severity, complications, related risk factors, duration of disease, medications, body mass index (BMI), fasting plasma glucose, and glycated hemoglobin (HbA1C) levels were assessed. The severity of diabetic gastroparesis was established using the disease-specific Patient Assessment of Gastrointestinal Disorders-Symptom Severity Index (PAGI-SYM) and the Gastroparesis Cardinal Symptom Index (GCSI). The five-point scale of the PAGI-SYM and the four-degree severity scores of GCSI were assessed. Neuropathy disability scores and motor evacuation functions were analyzed. Data were analyzed from these questionnaires, special proforma, and patient interviews. Results The clinical features of diabetic gastroparesis were observed in 44% of T2DM patients with mild-grade gastroparesis in 38 (21.7%), moderate in 30 (17.1%), and severe-grade gastroparesis-related symptoms in nine (5.2%) patients. The main manifestations were early satiety (45.1%), stomach fullness (44.5%), bloating (38.3%), and nausea (33.1%). Diabetic gastroparesis symptoms were considerably linked to disease duration of more than 10 years (p = 0.02), high HbA1c (p = 0.001), increased fasting blood glucose (p = 0.003), polyneuropathy, cigarette smoking, and history of comorbid conditions (p = 0.009). Obesity and the female gender were the forecasters of the manifestation of at least one cardinal gastroparesis symptom. Conclusions Gastric emptying is significant in the pathogenesis of gastroparesis-related symptoms. Disease duration of more than 10 years, poor glycemic control with hyperglycemia, high HbA1C, polyneuropathy, and cigarette smoking must be considered as predictors for early detection and risk factors for the advancement of gastroparesis in T2DM. Gastroparesis-related common symptoms of early satiety, bloating, and stomach fullness were considerably linked to the additional risk factors of hypercholesteremia, chronic microvascular complications, concomitant cardiovascular diseases, and a positive family history of diabetes mellitus. There was no relationship between BMI, age, types of treatment, and the degree of gastroparesis severity. The prevalence and severity of gastroparesis symptoms were particularly high among obese females with poor glycemic control and longer disease duration.

Gastroparesis: An Evidence-Based Review for the Bariatric and Foregut Surgeon

Gastroparesis is a gastric motility disorder characterized by delayed gastric emptying. It is a rare disease and difficult to treat effectively; management is a dilemma for gastroenterologists and surgeons alike. We conducted a systematic review of the literature to evaluate current diagnostic tools as well as treatment options. We describe key elements in the pathophysiology of the disease, in addition to current evidence on treatment alternatives, including nutritional considerations, medical and surgical options, and related outcomes.

Gastrointestinal Tract Considerations Part I

The upper gastrointestinal (GI) tract is frequently involved in systemic sclerosis (SSc) and may impact quality of life, physical function and survival. Although we are currently very proactive in terms of screening for heart and lung involvement, patients with SSc are not routinely screened for GI involvement. This review details the available investigations for common upper GI symptoms in SSc, including dysphagia, reflux and bloating and provides advice as to how to integrate these investigations into current clinical care.

Yunvjian Improves Glucose and Insulin Function in Diabetic Rats by Regulating Gastric Emptying Function

BACKGROUND

Diet acts on the human body through digestion in the stomach and absorption in the intestines. Thus, the emptying of the stomach should be the focus of the research mechanism of the combined medicine and food treatment of diabetes. The emptying function of the stomach and the secretion of related hormones may be the key points of traditional Chinese medicine. In the clinic, Yunvjian is a famous traditional Chinese formula for preventing and curing diabetes. However, the pharmacological action and mechanism of Yunvjian are also need to be probe.

OBJECTIVE

To assess the effect of Yunvjian on glucose, insulin level and gastric emptying function and related hormones on high-fat diet combined with STZ-induced diabetic rats.

METHODS

High-fat diet combined with STZ was used to construct type 2 diabetes mellitus (T2DM) rats model and received a 4-week Yunvjian administration. The animals were divided into 6 groups, respectively, as the Control group, the DM group, the DM + Acarbose group, the DM + YNH group, and the DM + YNL group. Radionuclide single-photon emission computed tomography (SPECT) technology was used to observe the gastric emptying rate and half-empty time; blood was took to test fasting insulin, and then the insulin resistance index (HOMA-IR) was calculated; HE staining was performed to detect islets and gastric antrum, immunohistochemical staining was performed to detect the number and morphology of pancreatic β cells and gastric antrum Cajal cells, and the average optical density was calculated; the expression of ghrelin hormone in gastric antrum and serum was detected by ELISA and immunofluorescence; the expression of GHRS mRNA in gastric antrum was detected by RT-PCR method.

RESULTS

Yunvjian could significantly improve the glucose level and insulin function of rats. Compared with the DM group, Yunvjian was beneficial to low fasting blood glucose (FBG) (P < 0.01), increased glucose tolerance, and improved islet function at the same time (P < 0.05). At the same time, compared with the DM group (25.02 ± 0.05, 44 ± 12.33), the emptying rate of the DM + YNH group was significantly faster (64.98 ± 0.12), and the half row time was shortened (26 ± 8.29, P < 0.05). The gastric ghrelin levels in each group of Yunvjian increased with different degrees compared with the DM group (616.2 ± 26.23), especially in the DM + YNH group (863.51 ± 23.76, P < 0.01). Correspondingly, the expression of gastric GHSR mRNA in the DM + YNH and DM + YNL groups increased significantly compared with the DM group (P < 0.01).

CONCLUSIONS

Yunvjian can effectively control glucose and improve islet function, which may be closely related to its influence on gastric emptying function and related hormone secretion regulation.

Self-assumed Neurologic Related Condition Deviated Metoclopramide-Induced Acute Dystonic of Oculogyric Crisis in a Woman of Childbearing Age: A Case Report

A 26-year-old Malaysian woman (childbearing age) attended a private primary care clinic with a known case of gastroesophageal reflux disease (GERD) and complained of persistent nausea and a few episodes of vomiting. She had no known drug allergy, no surgical history, no hospitalization in the last two years, was a non-smoker, and no history of drug or alcohol abuse. The patient was prescribed Tab metoclopramide 10 mg TDS and Tab ranitidine 150 mg BD for five days. About 30 min after oral administration of both medicines, her eyes rolled involuntary upward, leading to lateral deviation of the eyes, and mouth jaws clenched as if “dislocated jaws.” The patient was immediately brought into an emergency department (ED) of a public tertiary care hospital. A drug challenge test was done which resulted in the withdrawal of metoclopramide. The accompanied sister later disclosed that the patient had taken metoclopramide and ranitidine from a private clinic earlier in the day. The patient self-assumed to have a sudden seizure, due to excessive hot weather and dehydration. A slow intravenous infusion of 50 mg/mL diphenhydramine hydrochloride in 0.9% w/v NaCl 100 mL was administered stat. Consequently, the symptoms vanished after approximately 30 min of the therapy, devoid of relapse. The patient was discharged from ED post 8 hours of monitoring with complete recovery. Physicians frequently prescribe metoclopramide to treat nausea and vomiting, which may cause adverse drug reaction of acute dystonic oculogyric crisis (OGC). Due to its unwanted and unpredictable extrapyramidal symptoms, metoclopramide should be prescribed and dispensed with caution. Thorough history taking at ED is imperative for correct early diagnosis and treatment, as metoclopramide-induced dystonic OGC has a high probability of confusion with other causes of dystonia such as conversion and seizures, encephalitis, tetanus, and hypercalcemic tetany.

[Diabetic gastroenteropathy: modern methods of diagnosis and treatment]

Diabetes mellitus is a chronic disease with a growing prevalence worldwide, however, the prevalence of its complications, including gastroenteropathy, is also increasing. The pathophysiology of diabetic gastroenteropathy (DH) combines hyperglycemia, vagus nerve dysfunction, decreased expression of nitric oxide synthase in the myenteric plexus, changes in the interstitial Cajal cell network, as well as oxidative stress. Clinical signs of DH are gastroesophageal reflux, gastroparesis, constipation, abdominal pain and diarrhea. Among the diagnostic methods are manometry with pH measurement (assessment of esophageal motility), gastric emptying scintigraphy, respiratory test (to assess gastroparesis), aspiration and cultivation of the contents of the jejunum (to diagnose bacterial overgrowth syndrome). To date, there is no definitive treatment for DH - an interdisciplinary approach is aimed at slowing the progression of the disease, relieving symptoms and restoring gastrointestinal function. Patients are recommended a diet low in simple sugars and high in fiber; optimization of glycemic control with a target glycemia of less than 180 mg/dl. As for drug therapy, the use of prokinetics and antiemetics is justified, and in case of excessive bacterial growth syndrome, antibacterial therapy (rifaximin) is carried out. Modern approaches to the treatment of DH are also accumulating, including the use of botulinum toxin, pyloroplasty and electrical stimulation of the stomach in individual patients. Despite the constant development of new treatments, they are not yet able to completely cure DH in the near future, which makes it necessary to conduct further research in this area.

Diabetic Foot Ulcers and Cardiac Autonomic Neuropathy

PURPOSE

Diabetic foot ulcers (DFUs) and cardiac autonomic neuropathy (CAN) are severe complications of diabetes mellitus (DM). Both DFU and CAN are associated with increased risk of major cardiovascular events and mortality. Because of the clinical impact of both these conditions, it is important to establish what effect the presence of CAN has on DFU outcomes.

METHODS

This is a narrative review of original research articles identified through an electronic search of PubMed, Scopus, and Google scholar databases until June 2021 exploring CAN in individuals with DFUs. We explored prevalence, patient outcomes (DFU healing and amputation), and mortality.

FINDINGS

Evidence suggests that the prevalence of CAN is high, ranging from 43% to 66% among those with DFUs. The presence of CAN may also increase the odds of developing DFUs. A single-center, prospective, observational study has suggested that the presence of CAN significantly reduces DFU healing time. The impact on amputation is indeterminate, with conflicting reports from studies reporting either no or increased risk. On the basis of limited evidence, CAN may be associated with increased mortality in individuals with DFUs.

IMPLICATIONS

The interplay between CAN and DFUs is poorly understood from current literature. Given the high prevalence of CAN in individuals with DFUs and the potential for suboptimal outcomes, further high-quality studies are required to determine future management approaches when both conditions coexist and to establish whether early CAN screening in individuals with diabetes at high risk of foot ulceration may ultimately improve their outlook.

The efficacy and safety of Tuina for diabetic gastroparesis: A protocol for systematic review and meta-analysis

BACKGROUND

Diabetic gastroparesis (DGP) is one of the most common complication of diabetes. At present, despite the increasing number of clinical researches of treatment with Tuina have been reported, there are no systematic reviews of Tuina therapy for DGP. Therefore, it is of great significance to evaluate its safety and efficacy as a complementary and alternative therapy.

METHODS AND ANALYSIS

Randomized controlled trials (RCTs) of Tuina therapy in the treatment of DGP will be retrieved from PubMed, Embase, Web of Science, Cochrane Library, China National Knowledge Infrastructure (CNKI), Wan Fang Database (Wan Fang), Chinese Biomedical Literature Database (CBM), VIP Database for Chinese Technical Periodicals (VIP), Medline, and Clinical Trial Register (CTR). We will consider articles published in English or Chinese between database initiation and October 2021. Research selection, data extraction, risk of bias assessment, and meta-analyses will be independently completed by 2 researchers. Our researchers will use Revman 5.3 software, provided by the Cochrane Collaborative Network for conducting systematic reviews and meta-analysis.

RESULTS

This systematic review provides a high-quality synthesis to assess the effectiveness and safety of Tuina therapy for treating DGP.

CONCLUSION

The conclusions of our study will provide evidence to determine whether Tuina therapy is an effective and safe intervention for patients with DGP.

SYSTEMATIC REVIEW REGISTRATION

: INPLASY2021110019.

Roles of Endothelial Motilin Receptor and Its Signal Transduction Pathway in Motilin-Induced Left Gastric Artery Relaxation in Dogs

Background: Motilin increases left gastric artery (LGA) blood flow in dogs via the endothelial motilin receptor (MLNR). This article investigates the signaling pathways of endothelial MLNR.

Methods: Motilin-induced relaxation of LGA rings was assessed using wire myography. Nitric oxide (NO), and cyclic guanosine monophosphate (cGMP) levels were measured using an NO assay kit and cGMP ELISA kit, respectively.

Results: Motilin concentration-dependently (EC₅₀=9.1±1.2×10⁻⁸M) relaxed LGA rings precontracted with U46619 (thromboxane A₂ receptor agonist). GM-109 (MLNR antagonist) significantly inhibited motilin-induced LGA relaxation and the production of NO and cGMP. N-ethylmaleimide (NEM; G-protein antagonist), U73122 [phospholipase C (PLC) inhibitor], and 2-aminoethyl diphenylborinate [2-APB; inositol trisphosphate (IP₃) blocker] partially or completely blocked vasorelaxation. In contrast, chelerythrine [protein kinase C (PKC) inhibitor] and H89 [protein kinase A (PKA) inhibitor] had no such effect. Low-calcium or calcium-free Krebs solutions also reduced vasorelaxation. N-nitro-L-arginine methyl ester [L-NAME; nitric oxide synthase (NOS) inhibitor] and ODQ [soluble guanylyl cyclase (sGC) inhibitor] completely abolished vasodilation and synthesis of NO and cGMP. Indomethacin (cyclooxygenase inhibitor), 18α-glycyrrhetinic acid [18α-GA; myoendothelial gap junction (MEGJ) inhibitor], and K⁺ channel inhibition through high K⁺ concentrations or tetraethylammonium (TEA-Cl; K_Ca channel blocker) partially decreased vasorelaxation, whereas glibenclamide (K_ATP channel blocker) had no such effect.

Conclusion: The current study suggests that motilin-induced LGA relaxation is dependent on endothelial MLNR through the G protein-PLC-IP₃ pathway and Ca²⁺ influx. The NOS-NO-sGC-cGMP pathway, prostacyclin, MEGJ, and K⁺ channels (especially K_Ca) are involved in endothelial-dependent relaxation of vascular smooth muscle (VSM) cells.

MALAT1: A Pivotal lncRNA in the Phenotypic Switch of Gastric Smooth Muscle Cells via the Targeting of the miR-449a/DLL1 Axis in Diabetic Gastroparesis

Diabetic gastroparesis (DGP) is a common complication of diabetes mellitus (DM). Our previous study suggested that the expression of the long non-coding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is closely related to DGP. However, the role of MALAT1 in DGP pathogenesis remains unclear. Here, we aim to characterize the role of MALAT1 in DGP. First, we analyzed the lncRNA expression profiles through lncRNA sequencing. Next, we detected MALAT1 expression in the stomach tissues of DGP model mice and diabetic patients. Then, we investigated the role and mechanisms of MALAT1 in the proliferation, migration, phenotypic switch, and carbachol-induced intracellular Ca²⁺ changes in human gastric smooth muscle cells (HGSMCs) under high glucose (HG) conditions, using short hairpin RNA technology, RNA immunoprecipitation, and dual-luciferase reporter assays. We show that MALAT1 expression was upregulated in the gastric tissues of DGP model mice, the adjacent healthy tissues collected from diabetic gastric cancer patients with DGP symptoms, and in HGSMCs cultured under HG conditions. Functionally, MALAT1 knockdown in vitro impacted the viability, proliferation, migration and promoted the phenotypic switch of HGSMCs under HG conditions. Additionally, we show that MALAT1 sponged miR-449a, regulating Delta-like ligand 1 (DLL1) expression in HGSMCs; any disturbance of the MALAT1/miR-449a/DLL1 pathway affects the proliferation, migration, phenotypic switch, and carbachol-induced Ca²⁺ transient signals in HGSMCs under HG conditions. Collectively, our data highlight a novel regulatory signaling pathway, the MALAT1/miR-449a/DLL1 axis, in the context of DGP.

Diabetic gastroenteropathy: An underdiagnosed complication

This article is an extensive review that provides an update on the pathophysiology, symptoms, diagnosis, and treatment of diabetic gastroenteropathy. There is no reported prevalence, but it has been described that patients with type 1 diabetes have a cumulative incidence at 10 years of 5.2%, and type 2 patients, 1%. Also, in the group of type 1 diabetes, it has been observed that women are more likely to present this condition (5.8% vs 3.5%). Many factors are associate with its development (e.g., hyperglycemia, vagal dysfunction, loss of expression of neural nitric oxide synthase in the myenteric plexus, alterations in the Cajal interstitial cell network, and oxidative stress). Gastrointestinal discomfort could be perceived 70% higher in diabetic patients, describing that 25% of diabetic patients experience gastrointestinal symptoms. Diabetic enteropathy could affect any portion of the gastrointestinal tract, but esophageal alterations were described in more than 60% of diabetic patients, also 60% of them present constipation, and 20%, diarrhea. Gastric emptying scintigraphy is useful to evaluate gastroparesis, therefore, gastric retention of more than 60% at 2 h has a sensitivity of 100% and specificity of 20% for diagnosis; however, other studies such as breath tests, with a sensitivity of 89% and a specificity of 80%, or the endoscopic capsule contribute to the diagnosis. There is no cure; however, management must be multidisciplinary, focused on slowing the progression of diabetic gastroenteropathy, reducing symptoms, and restoring function; that includes nutritional recommendation, maintain glucose levels kept below 180 mg/dL, use of prokinetics, anti-emetics; nowadays, it has been special interest in surgical treatment, such as pyloroplasty, also gastric electrical stimulation appears to be another alternative.

Practical management approach to gastroparesis

Gastroparesis is a syndrome characterised by delayed gastric emptying in the absence of mechanical obstruction. Symptoms can include early satiety, abdominal pain, bloating, vomiting and regurgitation which cause significant morbidity in addition to nutritional deficits. There is a higher prevalence in diabetics and females, but the incidence in the Australian population has not been well studied. Management of gastroparesis involves investigating and correcting nutritional deficits, optimising glycaemic control and improving gastrointestinal motility. Symptom control in gastroparesis can be challenging. Nutritional deficits should be addressed initially through dietary modification. Enteral feeding is a second-line option when oral intake is insufficient. Home parenteral nutrition is rarely used, and only accessible through specialised clinics in the outpatient setting. Prokinetic medication classes that have been used include dopamine receptor antagonists, motilin receptor agonists, 5-HT₄ receptor agonists and ghrelin receptor agonists. Anti-emetic agents are often used for symptom control. Interventional treatments include gastric electrical stimulation, gastric per-oral endoscopic myotomy, feeding jejunostomy and gastrostomy/jejunstomy for gastric venting and enteral feeding. In this article we propose a framework to manage gastroparesis in Australia based on current evidence and available therapies.

Assessment of Gastrointestinal Autonomic Dysfunction: Present and Future Perspectives

The autonomic nervous system delicately regulates the function of several target organs, including the gastrointestinal tract. Thus, nerve lesions or other nerve pathologies may cause autonomic dysfunction (AD). Some of the most common causes of AD are diabetes mellitus and α-synucleinopathies such as Parkinson’s disease. Widespread dysmotility throughout the gastrointestinal tract is a common finding in AD, but no commercially available method exists for direct verification of enteric dysfunction. Thus, assessing segmental enteric physiological function is recommended to aid diagnostics and guide treatment. Several established assessment methods exist, but disadvantages such as lack of standardization, exposure to radiation, advanced data interpretation, or high cost, limit their utility. Emerging methods, including high-resolution colonic manometry, 3D-transit, advanced imaging methods, analysis of gut biopsies, and microbiota, may all assist in the evaluation of gastroenteropathy related to AD. This review provides an overview of established and emerging assessment methods of physiological function within the gut and assessment methods of autonomic neuropathy outside the gut, especially in regards to clinical performance, strengths, and limitations for each method.

Differences and Similarities in Neuropathy in Type 1 and 2 Diabetes: A Systematic Review

Background: Diabetic neuropathy is defined as the dysfunction of the peripheral nervous system in diabetic patients. It is considered a microvascular complication of diabetes mellitus. Its presence is associated with increased morbidity and mortality. Although several studies have found alterations at somatic motor, sensory levels and at the level of autonomic nervous system in diabetic patients, there is not a systematic approach regarding the differences in neuropathy between the major variants of diabetes, e.g., type 1 and 2 diabetes at both neurological and molecular level. Data sources: we systematically (Medline, Scopus, and Cochrane databases) evaluated the literature related to the difference of neuropathy in type 1 and 2 diabetes, differences in molecular biomarkers. Study characteristics: seventeen articles were selected based on pre-defined eligibility criteria. Conclusions: both superficial sensitivity (primarily thermal sensitivity to cold) and deep sensitivity (such as vibratory sensitivity), have been reported mainly in type 2 diabetes. Cardiac autonomic neuropathy is one of the diabetic complications with the greatest impact at a clinical level but is nevertheless one of the most underdiagnosed. While for type 1 diabetes patients most neuropathy alterations have been reported for the Valsalva maneuver and for the lying-to-standing test, for type 2 diabetes patients, alterations have been reported for deep-breathing test and the Valsalva test. In addition, there is a greater sympathetic than parasympathetic impairment, as indicated by the screening tests for autonomic cardiac neuropathy. Regarding subclinical inflammation markers, patients with type 2 diabetes showed higher blood levels of inflammatory markers such as high-sensitivity C-reactive protein, proinflammatory cytokines IL-6, IL-18, soluble cell adhesion molecules and E-selectin and ICAM-1, than in type 1 diabetes patients. By contrast, the blood levels of adiponectin, an adipocyte-derived protein with multiple paracrine and endocrine activities (anti-inflammatory, insulin-sensitizing and proangiogenic effects) are higher in type 1 than in type 2 diabetic patients. This review provides new insights into the clinical differences in type 1 and 2 diabetes and provide future directions in this research field.

Per-oral Endoscopic Myotomy and Other Applications of Third Space Endoscopy: Current Status and Future Perspectives

INTRODUCTION

The modification of NOTES (natural orifice transluminal endoscopic surgery) by mucosal safety flap has introduced us to the world of third space endoscopy (TSE). POEM (per-oral endoscopic myotomy) for achalasia cardia being its first vista, the realm expanded so that we can now remove en bloc a subepithelial/intramural tumor by POET (per-oral endoscopic tumor resection), perform G-POEM (gastric per-oral endoscopic myotomy) for refractory gastroparesis, restore esophageal continuity in complete obstruction by performing POETRE (per-oral endoscopic tunneling for the restoration of the esophagus), divide the septum in Zenker diverticulum completely with negligible risk of perforation by Z-POEM (Zenker per-oral endoscopic myotomy) and relieve constipation in Hirschsprung disease by PREM (per-rectal endoscopic myotomy). However, the real potential of TSE became evident with the introduction of POEM with fundoplication. TSE has opened the gates of the peritoneal cavity. Improved expertise and equipment will make the role of endoscopist complimentary to the surgeon with the dawn of a new field in therapeutic endoscopy.

AREAS COVERED

This review intends to comprehensively discuss the various aspects of POEM for achalasia studied so far followed by a brief discussion about other applications of TSE and the future perspectives in this exciting field.

An early scientific report on acromegaly: solving an intriguing endocrinological (c)old case?

We present and discuss a late-nineteenth century clinical case described by Professor Taruffi in a scientific paper titled "Scheletro con prosopoectasia e tredici vertebre dorsali" (Skeleton with prosopoectasia and thirteen thoracic vertebrae). Taruffi could not explain the disproportionate skeletal and visceral growth, and the case could therefore be considered an unrecognized case of acromegaly. The anatomopathological specimens and the wax model cited in the paper are currently hosted at the "Luigi Cattaneo" Anatomical Wax Collection of Bologna University; however, some inaccuracies and uncertainties as to their attribution to the same case have remained to this day. The skeletal remains were examined macroscopically to investigate any structural abnormalities and pathological changes. In addition, thanks to archival, museum inventory and literature research, we documented the systematic relationship between the paper and the samples and were able to ascribe the abnormally dilated dried stomach, currently displayed in a different showcase, to the same case. This is, to our knowledge, the first case of acromegaly in the history of medical literature which also includes a visceral specimen. As far as we know, there are no reports of the occurrence of severe gastromegaly in patients with acromegaly. In view of this rare association and, to date, endocrinological research, we hypothesize a further pathogenic mechanism by which acromegaly could have induced this massive dilatation. Taruffi's work represents an immensely valuable scientific/artistic heritage and is still cited in contemporary endocrinological literature, demonstrating its relevant contribution to the historical evolution of the disease through the nineteenth and twentieth centuries.

The efficacy and safety of acupoint injection for diabetic gastroparesis: A protocol for systematic review and meta-analysis

BACKGROUND

Diabetic gastroparesis (DGP) is one of the common complications of diabetes. Accumulated evidences have shown that acupoint injection is beneficial for the clinical treatment of diabetic gastroparesis. However, there is currently no systematic review to assess this therapy. This program aims to evaluate the effectiveness and safety of this therapy for the patients with DGP.

METHODS AND ANALYSIS

Literature search will be conducted via following electronic bibliographic databases from inception to Aug 2020: the Cochrane Library, PubMed, MEDLINE, Web of Science, EMBASE, Springer, China National Knowledge Infrastructure (CNKI), China Biology Medicine (CBM), Chinese Scientific Journal Database (VIP), Wan-Fang Database. All randomized controlled trials published in English or Chinese related to acupoint injection for DGP will be included. The primary outcome is the total effective rate. The secondary outcomes are the change of motilin and gastrin levels before and after the treatment. Two researchers will be responsible for the selection of study, extraction of data, and assessment of study quality independently. RevMan V5.3 Software will be used for assessing the risk of bias and synthesizing data.

RESULTS

This study will provide a high-quality synthesis of current available evidence for the treatment of DGP with this therapy clinically.

CONCLUSION

The conclusions of our study will provide new evidence to judge whether acupoint injection is an effective intervention for patients suffered from DGP. OSF REGISTRATION NUMBER:: osf.io/ms58j.

A microfabricated potentiometric sensor for metoclopramide determination utilizing a graphene nanocomposite transducer layer

In the recent drug analysis arena, optimizing a green, eco-friendly, and cost-effective technique is the main target. In order to cope with green analytical chemistry principles and the trending development of miniaturized portable and handheld devices, an innovative microfabricated ion-selective electrode for the analysis of metoclopramide (MTP) was developed. The fabricated electrode adopted a two-step optimization process. The first step of optimization depended on screening different ionophores in order to enhance the sensor selectivity. Calix-4-arene showed the maximal selectivity towards MTP. The second step was utilizing a graphene nanocomposite as an ion-to-electron transducer layer between the calix-4-arene polymeric membrane and the microfabricated copper solid-contact ion-selective electrode. The graphene nanocomposite layer added more stability to electrode potential drift and short response times (10 s), probably due to the hydrophobic behavior of the graphene nanocomposite, which precludes the formation of a water layer at the Cu electrode/polymeric membrane interface. The proposed MTP sensor has been characterized according to IUPAC recommendations and the linear dynamic range estimated to be 1 × 10^-6 to 1 × 10^-2 M with LOD of 3 × 10^-7 M. The proposed sensor has been successfully employed in the selective determination of MTP in bulk powder, pharmaceutical formulation, and biological fluid. No statistical significant difference was observed upon comparing the results with those of the official method. The Eco-score of the method was assessed using the Eco-Scale tool and was compared with that of the official method. Graphical abstract.

Efficacy and Safety of Ghrelin Agonists in Patients with Diabetic Gastroparesis: A Systematic Review and Meta-Analysis

Background/Aims

Ghrelin agonists are emerging prokinetic agents for treating gastroparesis. Although recent clinical trials have demonstrated their efficacy in patients with diabetic gastroparesis (DG), the impact of such agents on symptoms and gastric dysmotility remains unclear. We performed a systematic review and meta-analysis to evaluate the efficacy and safety of ghrelin agonists in patients with DG.

Methods

A search of common electronic databases (MEDLINE, Embase, and Cochrane Central Register of Controlled Trials) was preformed, using keyword combinations that referenced ghrelin and DG and retrieving all eligible randomized controlled trials (RCTs) of ghrelin agonists versus placebo in patients with DG. The primary outcome measure was the change in patient-reported overall gastroparesis symptom scores. Secondary outcomes included the change in gastric emptying time, specific symptoms related to gastroparesis, and adverse events. A random-effects model was applied to all study outcomes. Heterogeneity among studies was determined by the chi-square test and I² statistics.

Results

We selected six RCTs of patients with DG (n=557) for meta-analysis. Ghrelin agonist administration (vs placebo) significantly improved overall gastroparesis symptoms (standardized mean difference, –0.34; 95% confidence interval, –0.56 to –0.13) and significantly improved symptoms related to gastroparesis, including nausea, vomiting, early satiety, and abdominal pain. Adverse events recorded for ghrelin agonists and placebo did not differ significantly. There was no significant heterogeneity among eligible studies.

Conclusions

Compared with placebo, ghrelin agonists are effective and well-tolerated for the treatment of DG.

State-of-the-art pharmacotherapy for diabetic neuropathy

INTRODUCTION

The global epidemic of diabetes has led to an epidemic of diabetes complications. Diabetic neuropathy is the most common microvascular complication, of which diabetic peripheral neuropathy (DPN) and autonomic neuropathy (AN) are the most prevalent, affecting ~50% of patients. DPN results in pain with a poor quality of life and a loss of sensation with an increased risk of foot ulceration. Autonomic neuropathy can cause significant morbidity in a minority and is associated with increased mortality. The cornerstone of treatment to prevent or limit the progression of DPN/AN is multifactorial risk factor modification including treatment of glycemia, lipids and blood pressure. Whilst, there are no FDA-approved disease-modifying therapies, there are a number of therapies to relieve symptoms in DPN and AN.

AREAS COVERED

The authors discuss current approved therapies for painful diabetic neuropathy and autonomic neuropathy. They also address the potential role of improving risk factors to limit the development and progression of diabetic neuropathy and new pathogenetic and pain-relieving treatments.

EXPERT OPINION

The FDA-approved Pregabalin and Duloxetine over 25 years ago and Tapentadol, 6 years ago for painful diabetic neuropathy. There are currently no FDA-approved disease-modifying treatments for diabetic neuropathy which has been attributed to inappropriate models of the disease with limited translational capacity and major limitations of trial designs and endpoints in clinical trials.

Pathophysiology, Aetiology and Treatment of Gastroparesis

Gastroparesis is characterized by delayed gastric emptying, with symptoms such as nausea, vomiting and abdominal pain, in the absence of mechanical obstruction. In most cases, it is idiopathic although diabetes mellitus is another leading cause. The physiology of gastric emptying is a complex process which is influenced by various inputs including the central nervous system, enteric nervous system and gut hormones. Developments in our understanding of gastroparesis have now demonstrated dysfunction in these systems, thus disrupting normal gastric emptying. Once mechanical obstruction is excluded, gastric scintigraphy remains the gold standard for diagnosis although wireless motility capsule and breath testing are alternative methods for diagnosis. Treatment for gastroparesis is challenging, and widely available therapies are often limited either by their poor evidence for efficacy or concerns over their long-term safety profile. Novel prokinetic agents have shown initial promise in clinical trials, and new endoscopic techniques such as gastric per-oral endoscopic myotomy are emerging. These new treatment modalities may provide an option in refractory gastroparesis with the adage of reduced morbidity compared to surgical treatments.

Therapies for diabetic gastroparesis: A protocol for a systematic review and network meta-analysis

BACKGROUND

Diabetic gastroparesis (DG) is a common autonomic neuropathy which impacts on nutritional state and quality of life in diabetic patients, and it also adversely affects glycemic control in diabetes. The prevalence of DG is growing with the number of patients with diabetes continues to increase. However, there is no definitive answer as to which of the current therapies is the best for the clinical treatment of the different manifestations of DG. The subject of this study is to answer the following question: what is the best intervention for diabetic patients with gastroparesis?

METHODS

Comprehensive searches of the Cochrane Library, PubMed, Embase, Medline, Central and Web of Science, and 4 Chinese databases, including China National Knowledge Infrastructure, VIP Database for Chinese Technical Periodicals, Chinese Biomedical Literature Database, and WanFang will be completed using the following keywords DG and therapies and related entry terms. Studies will be included, according to the eligibility criteria (randomized controlled trials and controlled clinical trials, considering specific outcome measures for DG). The reference lists of included studies will be manual searched. Relevant data will be extracted from included studies using a specially designed data extraction sheet. Risk of bias of the included studies will be assessed, and the overall strength of the evidence will be summarized through GRADE. A random effects model will be used for all pairwise meta-analyses (with a 95% confidence interval). A Bayesian network meta-analysis will explore the relative benefits between the various therapies. The review will be reported using the Preferred Reporting Items for Systematic Reviews incorporating Network Meta-Analyses statement. Network meta-analysis will be performed using a Bayesian framework through the Winbugs software.

RESULTS

This network meta-analysis will identify the best effective therapy for DG.

CONCLUSION

This study will compare and evaluate current therapies for DG, and find the best treatment of DG.

Ingestible Sensors and Sensing Systems for Minimally Invasive Diagnosis and Monitoring: The Next Frontier in Minimally Invasive Screening

Ingestible electronic systems that are capable of embedded sensing, particularly within the gastrointestinal (GI) tract and its accessory organs, have the potential to screen for diseases that are difficult if not impossible to detect at an early stage using other means. Furthermore, these devices have the potential to (1) reduce labor and facility costs for a variety of procedures, (2) promote research for discovering new biomarker targets for associated pathologies, (3) promote the development of autonomous or semiautonomous diagnostic aids for consumers, and (4) provide a foundation for epithelially targeted therapeutic interventions. These technological advances have the potential to make disease surveillance and treatment far more effective for a variety of conditions, allowing patients to lead longer and more productive lives. This review will examine the conventional techniques, as well as ingestible sensors and sensing systems that are currently under development for use in disease screening and diagnosis for GI disorders. Design considerations, fabrication, and applications will be discussed.

Single‑strained DNA aptamers mask RhD antigenic epitopes on human RhD+ red blood cells to escape alloanti‑RhD immunological recognition

Rhesus D‑ (RhD‑) individuals should receive Rh‑matched blood to prevent hemolytic anemia. However, there is a shortage of RhD‑ blood. This study aimed to generate RhD antigen‑specific single‑stranded DNA (ssDNA) aptamers, and test their efficacy in masking RhD antigens on RhD+ red blood cells (RBCs) to prevent their immunoreactivity in vitro. In the present study, ssDNA aptamer candidates were synthesized as a central randomized sequence of 40 nucleotides (nt) flanked by 21‑nt primer hybridization sequences. The functional aptamers were screened using the cell‑based systematic evolution of ligands by exponential enrichment technique and RhD+ RBCs. Two bioactive ssDNA aptamers significantly inhibited the binding of an anti‑RhD antibody to RhD+ RBCs and bound to RhD antigens with high affinity (dissociation constant values of 580.5±142.0 and 737.7±161.8 nM, respectively). Furthermore, treatment with both ssDNA aptamers (500 pmol) effectively masked RhD antigens on 4,000,000 RhD+ RBCs to prevent human anti‑RhD alloantibody‑mediated binding, RBC agglutination and monocyte recognition in vitro. Collectively, such data suggested that these ssDNA aptamers may be feasible for masking RhD antigens on RBCs, and thus valuable for prevention or at least amelioration of RhD+‑related hemolytic anemia in RhD‑ individuals.

Pharmacological Approaches to Diabetic Gastroparesis: A systematic review of randomised clinical trials

Pharmacological interventions of diabetic gastroparesis (DG) constitute an essential element of a patient’s management. This article aimed to systematically review the available pharmacological approaches of DG, including their efficacy and safety. A total of 24 randomised clinical trials (RCTs) that investigated the efficacy and/or safety of medications targeting DG symptoms were identified using several online databases. Their results revealed that metoclopramide was the only approved drug for accelerating gastric emptying and improving disease symptoms. However, this medication may have several adverse effects on the cardiovascular and nervous systems, which might be resolved with a new intranasal preparation. Acceptable alternatives are oral domperidone for patients without cardiovascular risk factors or intravenous erythromycin for hospitalised patients. Preliminary data indicated that relamorelin and prucalopride are novel candidates that have proven to be effective and safe. Future RCTs should be conducted based on unified guidelines using universal diagnostic modalities to reveal reliable and comprehensive outcomes.

Vagus Nerve Stimulation at the Interface of Brain-Gut Interactions

The vagus nerve, a key component of the cross-communication between the gut and the brain, is a major element of homeostasis sensing the "milieu intérieur" and boosting the nervous and endocrine responses to maintain the gastrointestinal health status. This nerve has anti-inflammatory properties regulating the gut through the activation of the hypothalamic-pituitary-adrenal axis and the release of cortisol and through a vagovagal reflex, which has an anti-tumor necrosis factor (TNF) effect called the cholinergic anti-inflammatory pathway. Stimulating this nerve is an interesting tool as a nondrug therapy for the treatment of gastrointestinal diseases in which brain-gut communication is dysfunctional, such as inflammatory bowel disorders and others. This review presents the rationale of vagal gastrointestinal physiology and diseases and the most recent advances in vagus nerve stimulation. It also highlights the main issues to be addressed in the future to improve this bioelectronic therapy for gastrointestinal disorders.

An update on the diagnosis and treatment of diabetic somatic and autonomic neuropathy

Diabetic peripheral neuropathy (DPN) is the most common chronic complication of diabetes. It poses a significant challenge for clinicians as it is often diagnosed late when patients present with advanced consequences such as foot ulceration. Autonomic neuropathy (AN) is also a frequent and under-diagnosed complication unless it is overtly symptomatic. Both somatic and autonomic neuropathy are associated with increased mortality. Multiple clinical trials have failed because of limited efficacy in advanced disease, inadequate trial duration, lack of effective surrogate end-points and a lack of deterioration in the placebo arm in clinical trials of DPN. Multifactorial risk factor reduction, targeting glycaemia, blood pressure and lipids can reduce the progression of DPN and AN. Treatment of painful DPN reduces painful symptoms by about 50% at best, but there is limited efficacy with any single agent. This reflects the complex aetiology of painful DPN and argues for improved clinical phenotyping with the use of targeted therapy, taking into account co-morbid conditions such as anxiety, depression and sleep disturbance.

Diagnosing and managing diabetic somatic and autonomic neuropathy

The diagnosis and management of diabetic neuropathy can be a major challenge. Late diagnosis contributes to significant morbidity in the form of painful diabetic neuropathy, foot ulceration, amputation, and increased mortality. Both hyperglycaemia and cardiovascular risk factors are implicated in the development of somatic and autonomic neuropathy and an improvement in these risk factors can reduce their rate of development and progression. There are currently no US Food and Drug Administration (FDA)-approved disease-modifying treatments for either somatic or autonomic neuropathy, as a consequence of multiple failed phase III clinical trials. While this may be partly attributed to premature translation, there are major shortcomings in trial design and outcome measures. There are a limited number of partially effective FDA-approved treatments for the symptomatic relief of painful diabetic neuropathy and autonomic neuropathy.