Optimising Insulin Injection Techniques to Improve Diabetes Outcomes.

The effectiveness of therapy in patients with diabetes depends on the correct use of the insulin injection technique. However, despite many established recommendations and evidence that an effective insulin injection technique is essential to improve glycaemic control and minimise the risk associated with diabetes, there is still a need to identify impediments to the insulin injection technique among patients and create awareness among patients and healthcare professionals about the importance of the optimisation of insulin injection techniques. This review focuses on the recent advancements in delivery devices, insulin injection technique teaching methods, monitoring, and complication management and highlights regional best practices and recommendations for optimising injection techniques to improve diabetes outcomes.

[Insulin-derived amyloidosis (insulin ball) and skin-related complications of insulin therapy].

Skin-related complications of insulin therapy have long been a problem as a factor interfering with insulin therapy. Among the traditional skin-related complications, lipoatrophy and insulin allergy have decreased markedly with the development of insulin preparations, but lipohypertrophy is still common in insulin-treated patients. Recently, there have been more reports of a skin-related complication called insulin-derived amyloidosis or insulin ball. Insulin-derived amyloidosis is a condition in which injected insulin becomes amyloid protein and is deposited at the injection site. Insulin-derived amyloidosis causes poor glycemic control and increased insulin dose requirements, which are caused by decreased insulin absorption. Lipohypertrophy also decreases insulin absorption, but insulin-derived amyloidosis causes a more significant decrease in insulin absorption and has a greater clinical impact. Therefore, it is important to make a differential diagnosis between insulin-derived amyloidosis and lipohypertrophy, but sometimes it is difficult to distinguish the two and imaging studies are required. The diagnosis of insulin-derived amyloidosis is often difficult in the general practice, and its pathogenesis and prevalence have not been fully clarified. Recently, it has been reported that insulin-derived amyloidosis can be toxic, suggesting an association with minocycline use. The treatment of insulin-derived amyloidosis and lipohypertrophy is to avoid the site of amyloidosis or lipohypertrophy and inject insulin, but the dose of insulin injection should be reduced. Prevention of both insulin-derived amyloidosis and lipohypertrophy is important, and for this purpose, observations of the insulin injection site and instruction on appropriate insulin injection techniques are necessary, and multidisciplinary cooperation is extremely important.

Multiple Endocrine Neoplasia Type 1 with Functional Parathyroid Cysts.

A 51-year-old woman was admitted because of hypercalcemia. Neck ultrasonography and computed tomography revealed the presence of parathyroid cysts on both sides. After primary hyperparathyroidism was diagnosed by technetium-99m-methoxyisobutylisonitrile scintigraphy, the patient was successfully treated with total parathyroidectomy and autotransplantation. She also had a non-functioning pancreatic neuroendocrine tumor, prolactinoma, and adrenal tumors with subclinical Cushing's syndrome. Given these clinical features and her family history, multiple endocrine neoplasia type 1 (MEN1) was suspected, and germline DNA sequencing revealed a missense mutation (c.1013T>C, [corrected] p.Leu338Pro) in exon 7 of MEN1. This case demonstrates the phenotypic and genetic diversity of MEN1.

A case of nonislet cell tumor hypoglycemia associated with malignant mesothelioma requiring a multifaceted approach for optimal glycemic control.

Nonislet tumor hypoglycemia (NICTH) is a rare paraneoplastic syndrome characterized by refractory hypoglycemia, which often requires multifaceted therapy. We reported a case of a patient with pleural malignant mesothelioma and developed NICTH, for which chemotherapy, glucocorticoids, and nutrition were given to achieve optimal glycemic control.

Degradation of insulin amyloid by antibiotic minocycline and formation of toxic intermediates.

Insulin balls, localized insulin amyloids formed at subcutaneous insulin-injection sites in patients with diabetes, cause poor glycemic control owing to impairments in insulin absorption. Our previous study has shown that some insulin balls are cytotoxic, but others are not, implying amyloid polymorphism. Interestingly, the patient with toxic insulin balls had been treated with antibiotic minocycline, suggesting a possible relationship between toxicity of insulin balls and minocycline. However, the direct effect of minocycline on the structure and cytotoxicity of the insulin amyloid is still unclear. Herein, we demonstrated that that minocycline at physiological concentrations induced degradation of insulin amyloids formed from human insulin and insulin drug preparations used for diabetes patients. Interestingly, the process involved the initial appearance of the toxic species, which subsequently changed into less-toxic species. It is also shown that the structure of the toxic species was similar to that of sonicated fragments of human insulin amyloids. Our study shed new light on the clarification of the revelation of insulin balls and the development of the insulin analogs for diabetes therapy.

Insulin amyloid polymorphs: implications for iatrogenic cytotoxicity.

Amyloid specific fluorescent probes are becoming an important tool for studies of disease progression and conformational polymorphisms in diseases related to protein misfolding and aggregation such as localized and systemic amyloidosis. Herein, it is demonstrated that using the amyloid specific fluorescent probes pFTAA and benzostyryl capped benzothiadiazole BTD21, structural polymorphisms of insulin amyloids are imaged in localized insulin-derived amyloid aggregates formed at subcutaneous insulin-injection sites in patients with diabetes. It is also found that pFTAA and BTD21 could discriminate structural polymorphisms of insulin amyloids, so called fibrils and filaments, formed in vitro. In addition, it is shown that insulin drug preparations used for treating diabetes formed various types of amyloid aggregates that can be assessed and quantified using pFTAA and BTD21. Interestingly, incubated pFTAA-positive insulin preparation aggregates show cytotoxicity while BTD21-positive aggregates are less toxic. From these observations, a variety of amyloid polymorphic structures with different cytotoxicities formed both in vivo and in vitro by various insulin preparations are proposed.

Insulin-derived amyloidosis without a palpable mass at the insulin injection site: A report of two cases.

To date, almost all case reports of insulin-derived amyloidosis described the presence of a subcutaneous mass that was observable on physical examination. This report presents two cases of insulin-derived amyloidosis without palpable masses at insulin injection sites. In both cases, blood glucose concentrations improved, and the insulin dose could be reduced by an average of 45% after changing the insulin injection sites. The insulin absorption at the site was reduced to at most 40% of that at a normal site in one case. Magnetic resonance imaging and ultrasonography were useful to screen and differentiate insulin-derived amyloidosis without a palpable mass. This report showed that insulin-derived amyloidosis without a palpable mass can be present at the insulin injection site, and has similar clinical effects to insulin-derived amyloidosis with palpable masses.

Toxicity of insulin-derived amyloidosis: a case report.

BACKGROUND: Insulin-derived amyloidosis is a skin-related complication of insulin therapy that interferes with insulin therapy. Although toxicities of in vitro-formed insulin amyloid fibrils have been well studied, the toxicity of insulin-derived amyloidosis remains to be clarified. CASE PRESENTATION: A 58-year-old man with type 2 diabetes mellitus underwent a lower limb amputation due to diabetic gangrene. Several antibiotics including minocycline were administered for infection and sepsis. A hard mass at the insulin injection sites in the lower abdomen was discovered by chance four months later. Although no abnormal findings in the surface skin of the mass were observed, necrotic tissue was seen around the mass when a biopsy was performed. Histological and toxicity studies were performed for this patient and four other patients with abdominal masses at insulin injection sites. Histological and immunohistochemical studies showed that the masses had typical characteristics of amyloid deposits in all cases, whereas necrotic findings were seen adjacent to the amyloid deposit only in the case presented. Toxicity studies indicated that the amyloid tissue from the present case had significant cell toxicity compared to the control skin tissue or the amyloid tissues from the other four cases. CONCLUSIONS: This report showed that toxic insulin-derived amyloidosis can occur. In addition, this report suggested that toxic insulin-derived amyloidosis may cause necrosis in the surrounding tissue. Although the toxic amyloid deposit of insulin-derived amyloidosis was found in only one patient, no structural differences between toxic and non-toxic deposits were seen on histological and immunohistochemical studies.

In vitro studies on nobiletin isolated from citrus plants and the bioactive metabolites, inhibitory action against gelatinase enzymatic activity and the molecular mechanisms in human retinal Müller cell line.

Diabetic retinopathy (DR) is the most common cause of vision loss in patients with diabetes mellitus. Despite the presence of effective therapy, DR is still a significant health burden. A recent research suggests that matrix metalloproteinases (MMPs) could be promising targets, which exert multiple actions on early- and late-stage pathogenesis of DR. Among the MMP family, gelatinases (MMP-2 and MMP-9) act as potent proinflammatory, proangiogenic, and pro-apoptotic factors. Therefore, the pharmacological inhibitory effect of gelatinases on retinal MMP-producing cells may be useful in the treatment or prevention of DR. Nobiletin isolated from citrus plants is a multi-functional polymethoxylated flavone, which exerts biological effects including inhibitory action against MMP activity in several cancer cells. In the present study, we demonstrated that nobiletin isolated from citrus plants attenuated MMP-9 enzymatic activity through the suppression of transcription for MMP-9 gene expression and augmentation of TIMP-1 production in retinal Müller cells. Nobiletin regulated MMP-9 gene expression and TIMP-1 by inhibiting the PI3K/Akt signaling pathway. In addition, we observed the augmentation of inhibitory action against MMP-9 enzymatic activity by 4'-demethylated nobiletin, which is a major metabolite of nobiletin. We believe that the enhancement of inhibitory action against MMP-9 enzymatic activity by 4'-demethylated nobiletin is through the dual inhibition on Erk1/2 and Akt phosphorylation. The structure-activity relationship analysis revealed that, for the enhancement of inhibitory action against MMP-9 enzymatic activity, demethylation at position 4' in B-ring was a key structural modification in Müller cells, which are an important source of MMPs found in vitreous fluid and retinal tissues in retinal proliferative diseases. These results suggested that nobiletin, derived from a natural source, may serve as a novel MMP inhibitor with minimal side effects, and lead compound for the design of more efficacious drugs.

Novel screening for transthyretin amyloidosis by using fat ultrasonography.

We aimed to assess the possibility of using a noninvasive screening method for hereditary transthyretin amyloidosis by means of abdominal fat ultrasonography. Quantitative analysis of ultrasound B-mode images demonstrated a significant increase in mean echogenicity and a loss of the normal structure of the layers of fat tissue in patients with hereditary transthyretin amyloidosis (n = 19). The ultrasound features of the fat tissue and the degree of amyloid deposition seen histopathologically showed a significant correlation. These results suggest that abdominal fat ultrasonography may be a valuable method for screening for hereditary transthyretin amyloidosis. Ann Neurol 2017;81:604-608.

Insulin-derived amyloidosis and poor glycemic control: a case series.

OBJECTIVES: Insulin-derived amyloidosis is a rare skin-related complication of insulin therapy. The purpose of this study was to show the effects of insulin-derived amyloidosis on blood glucose levels, insulin dose requirements, and insulin absorption. METHODS: Seven patients were found to have insulin-derived amyloidosis at the Tokyo Medical University Ibaraki Medical Center. The clinical characteristics and insulin therapy of the 7 patients were investigated. Insulin absorption was studied by comparing the serum insulin levels after insulin injections into insulin-derived amyloidosis sites versus injections into normal sites in 4 patients. RESULTS: When the insulin-derived amyloidosis was discovered, the mean hemoglobin A1c level was 9.3%, and the mean daily insulin dose was 57 units. After changing the injection sites to avoid the insulin-derived amyloidosis, the blood glucose concentrations improved, and the mean daily insulin dose could be reduced to 27 units (P = .035; 53% reduction). The insulin absorption at insulin-derived amyloidosis sites was 34% of that at normal sites (P = .030). CONCLUSIONS: Insulin-derived amyloidosis caused poor glycemic control and increased insulin dose requirements because of impairments in insulin absorption.

Cell-mediated contraction of vitreous explants from chicken embryo: possibility of screening for therapeutic agents against proliferative vitreoretinal diseases.

PURPOSE: We aimed to establish a novel screening system for identifying potential therapeutic agents for treating proliferative vitreoretinal diseases (PVDs). In this study, we focused on vitreous explants from chicken embryos and evaluated the usefulness of quantitatively analyzing the effects of potential candidates on cell-mediated vitreous contraction, which leads to blindness in PVDs. METHODS: Vitreous explants were extracted from 19-day-old embryonic chickens and then incubated with retinal Müller cells or endothelial cells to permit cell adhesion. After cell adhesion occurred, we examined the effect of the attached cells on the wet weight of vitreous explants as an index of vitreous contraction. We also performed hematoxylin and eosin staining to characterize the cell morphology on the vitreous surface. RESULTS: Contraction of the vitreous explants was observed after cell adhesion of not only retinal Müller cells but also endothelial cells. We confirmed the adhesion of these cells on vitreous explants and estimated the number of adherent cells with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) analysis. The cells on the vitreous surface presented an elongated fibroblast-like phenotype. Integrin was found to be a receptor involved in cell adhesion on the vitreous surface. DISCUSSION: Our results suggest that vitreous explants from chicken embryos may be novel useful tools for screening antiadhesion therapeutic agents in PVDs. This preliminary study must be validated with human vitreous and human retinal pigment epithelial cells.

Protein kinase C-mediated regulation of matrix metalloproteinase and tissue inhibitor of metalloproteinase production in a human retinal müller cells.

PURPOSE: Matrix metalloproteinases (MMPs) play an important role in the degradation of extracellular matrix (ECM) proteins in the retina. Breakdown of ECM proteins results in neovascularization and tractional retinal detachment, which eventually lead to the symptoms of proliferative diabetic retinopathy. Müller cells are reported to be one of the MMP-producing cells in the retina. However, the molecular mechanism of MMP production derived from Müller cells remains to be fully elucidated. MATERIALS AND METHODS: The human retinal Müller cell line (MIO-M1) was continuously-subcultured in high glucose (25 mM) condition. After the cells reached confluence, they were treated for 24 h with phorbol ester and/or a protein kinase C (PKC) inhibitor, GF109203X in high (25 mM) or low (5 mM) glucose condition. Gelatinase activities in conditioned medium were assessed using gelatin zymography. RT-PCR was performed to analyze the mRNA expression level of MMP-9. Western blot analysis used to detect the protein expression of tissue inhibitors of metalloproteinases (TIMPs). Electrophoresis mobility shift assay was conducted to examine transcription factors involved in MMP-9 transcription. RESULTS: We demonstrated the protein kinase C (PKC)-mediated regulation of proMMP-9 transcription and protein expression through the action of phorbol ester, an activator of PKC. Moreover, we demonstrated the expression of TIMPs, known as natural inhibitors of MMPs at the protein level in a human retinal Müller cell line for the first time, and report that production of these proteins was also regulated in a PKC-dependent manner. CONCLUSION: Our results suggest that imbalance between MMP and TIMP proteins may promote neovascularization by PKC activation in retinal Müller cells. In addition, the development of novel compounds with regulatory action on MMP and TIMP production through inhibiting PKC activity in retinal Müller cells may lead to new therapeutic approaches for the treatment and prevention of diabetic retinopathy.

Examination of candidate chromosomal regions for type 2 diabetes reveals a susceptibility locus on human chromosome 8p23.1.

In a panel of large Caucasian pedigrees, we genotyped markers in eight chromosomal regions previously reported as supporting linkage with type 2 diabetes. We previously reported significant linkage on chromosome 20q (maximum logarithm of odds score [MLS] = 2.79) in this panel. In the present analysis, candidate regions on 1q, 2q, 3q, 5q, 9q, and 10q yielded little evidence for linkage; a region on 2p (MLS = 1.64, P = 0.01 at position 9.0 cM) gave suggestive evidence of linkage; and a region on 8p (MLS = 3.67, P = 2.8 x 10(-5), at position 7.6 cM) gave significant evidence of linkage. Conditional analyses were performed for both 2p and 8p regions and the region reported on 20q. The MLS for 2p increased from 1.64 to 1.79 (empirical P = 0.142) when conditioned for heterogeneity on 20q. The case was similar for 8p, where the MLS increased from 3.67 to 4.51 (empirical P = 0.023) when conditioned on families without evidence of linkage at 20q. In conclusion, our data support a type 2 diabetes susceptibility locus on chromosome 8p that appears to be independent from other susceptibility loci. Although we were able to replicate linkage in our pedigrees on chromosome 2p, we did not find evidence of linkage for regions on 1q, 2q, 3q, 5q, 9q, or 10q.

A family of autosomal dominant hypocalcemia with a positive correlation between serum calcium and magnesium: identification of a novel gain of function mutation (Ser(820)Phe) in the calcium-sensing receptor.

To date about 20 activating mutations in the calcium-sensing receptor (CaR) gene have been identified to cause autosomal dominant hypocalcemia (ADH) or sporadic hypoparathyroidism. We report a novel activating mutation in the CaR gene in a Japanese family with ADH. The proband, a 15-yr-old boy, and 5 other patients in 3 generations were asymptomatic, except for the proband's grandmother who had a history of seizures. They showed mild hypocalcemia (1.68-1.98 mmol/liter) with normal urinary calcium excretion and low normal serum PTH levels. Their serum magnesium concentrations were below normal in 3 adults and within the normal range in 3 teenagers. There was a significant positive correlation (r = 0.90; P < 0.05) between the serum calcium and magnesium concentrations of 6 affected members. Nucleotide sequencing revealed that the proband had a known polymorphism (Gly(990)Arg) and a novel heterozygous mutation substituting phenylalanine for serine at codon 820 (Ser(820)Phe) in the sixth transmembrane helix of the CaR. In other family members, the Ser(820)Phe mutation cosegregated with hypocalcemia. The mutation was not detected in 50 control subjects. The Gly(990)Arg polymorphism was observed in 8 of 9 family members with or without hypocalcemia and in 36 of 50 controls. The sensitivity of the Ser(820)Phe mutant CaR to calcium was assessed using transiently transfected HEK293 cells and measuring the increases in intracellular Ca(2+) concentrations in response to the changes in extracellular Ca(2+). The concentration-response curve of the mutant receptor was left-shifted, and its EC(50) (2.5 mM) was significantly (P < 0.05) lower than that of the wild-type CaR (3.3 mM). We conclude that the Ser(820)Phe mutation in the CaR caused ADH in this family. The positive correlation between serum calcium and magnesium levels observed in this family may support the concept that renal CaR acts as a magnesium sensor as well as a calcium sensor.

Assessment of diabetic autonomic neuropathy using twenty-four-hour spectral analysis of heart rate variability: a comparison with the findings of the Ewing battery.

A power spectral analysis of heart rate variability has been applied in order to assess diabetic autonomic neuropathy and high frequency spectra are thus considered to possibly reflect vagal nerve integrity in patients with diabetes mellitus. The purpose of this study was to investigate the relationship between the findings of high frequency spectra analysis and the results of the Ewing battery. We performed 24-hour power spectral analysis using an ambulatory ECG monitoring system and standard tests in order to assess diabetic autonomic neuropathy (Ewing battery) in 18 diabetic patients to compare their diagnostic values for diabetic autonomic neuropathy. We used the high frequency amplitude (high frequency spectra; 0.15-0.40 Hz) as a direct measure of vagal nerve integrity from each hourly spectral plot. All hourly high frequency spectra decreased along with the impaired assessment of the battery, especially during the night when the high frequency spectra showed a manifest increase in patients classified as normal according to the battery. High frequency spectra during the night while asleep (22:00-05:00) and during a 24-hour period significantly correlated with the results of the battery. These values markedly decreased even in patients classified as having early vagal damage when compared with those classified as normal. High frequency spectra during night closely reflected the intrinsic vagal nerve integrity in patients with diabetes mellitus. High frequency spectra during night or a 24-hour period is a simple and sensitive measure of diabetic autonomic neuropathy and is considered to be a useful modality for detecting even early changes in autonomic dysfunction.