Study protocol for assessment of the efficacy of calcium dobesilate versus placebo on SARS-CoV-2 viral load in outpatients with COVID-19 (CADOVID study): a randomised, placebo-controlled, double-blind, monocentric phase II trial.

INTRODUCTION: SARS-CoV-2 mainly infects respiratory endothelial cells, which is facilitated through its spike protein binding to heparan sulphate. Calcium dobesilate (CaD) is a well-established, widely available vasoactive and angioprotective drug interacting with heparan sulphate, with the potential to interfere with the uptake of SARS-CoV-2 by epithelial cells. The CADOVID trial aims to evaluate the efficacy and safety of CaD in reducing the SARS-CoV-2 viral load in non-hospitalised adult patients diagnosed with COVID-19, confirmed by a positive SARS-CoV-2 PCR, including its efficacy to reduce the impact of persistent COVID-19 symptoms. METHODS AND ANALYSIS: This is a randomised, placebo-controlled, double-blind, monocentric phase II trial. Enrolment began in July 2022. A total of 74 adult patients will be randomly allocated to the CaD arm or the placebo group with a 1:1 ratio, respectively. Participants in the intervention arm will receive two capsules of CaD 500 mg two times per day and the placebo arm will receive two matching capsules of mannitol 312.5 mg two times per day, with a treatment period of 7 days for both arms, followed by a 77-day observational period without treatment administration. Participants will be asked to complete secured online questionnaires using their personal smartphone or other electronic device. These include a COVID-19 questionnaire (assessing symptoms, temperature measurement, reporting of concomitant medication and adverse events), a COVID-19 persistent symptoms' questionnaire and the Short Form 12-Item (SF-12) survey. SARS-CoV-2 PCR testing will be performed on nasopharyngeal swabs collected on days 1, 4, 8 and 21. The primary endpoint is the reduction from baseline of SARS-CoV-2 viral load determined by RT-PCR at day 4. ETHICS AND DISSEMINATION: This trial has received approval by the Geneva Regional Research Ethics Committee (2022-00613) and Swissmedic (701339). Dissemination of results will be through presentations at scientific conferences and publication in scientific journals. TRIAL REGISTRATION NUMBER: NCT05305508; Clinicaltrials.gov; Swiss National Clinical Portal Registry (SNCTP 000004938).

Investigation of therapeutic effects of calcium dobesilate in cerebral hypoxia/ reperfusion injury in rats.

OBJECTIVES: Cerebral stroke is a serious clinical condition in which oxidative stress, inflammation, necrosis, apoptosis, and autophagy play important roles in its pathogenesis. This study investigated the neuroprotective and healing effects of calcium dobesilate (CD) on cerebral hypoxia/reperfusion injury in rats. METHODS: Forty Wistar albino male rats, each weighing 300-350 g, were separated into the Control group (no surgery and no pharmacological agent was administered); Sham-A group (only surgery was performed); DBL-A group (surgery was performed and CD 100 mg/kg/day was administered intraperitoneally for 3 days); Sham-C group (only surgery was performed); and DBL-C group (surgery was performed and 100 mg/kg/day CD was administered intraperitoneally for 10 days). Under sedation anesthesia, the bilateral common carotid arteries of all rats except the Control group were clipped for 30 min. After 4 h, the CD was given to the relevant groups, and then, all subjects were euthanized at scheduled times. The brain of each animal was removed for histopathological (hematoxylin and eosin staining), immunohistochemical (beclin-1, anti-MHC class II and anti-CD-68 staining), and biochemical (TNF, IL-1ß, IL-6, caspase-3, GSH/GSSG, malondialdehyde, protein carbonyl, LC3II/LC3I, and beclin-1 levels) evaluations. RESULTS: It was observed that CD could reduce necrosis and mitigate polarization of microglia to the M1 phenotype, autophagy, free oxygen radicals, protein carbonylation, lipid peroxidation, IL-1ß, IL6, TNF, caspase-3, beclin-1, and LC3II/LC3I levels in acute and chronic periods of hypoxia/reperfusion injury. CONCLUSION: From these results, it was observed that CD treatment could reduce neuronal necrosis and create anti-inflammatory, anti-edema, anti-oxidant, anti-apoptotic, and anti-autophagic effects in hypoxia/reperfusion injury in rats.

Intravitreal Ranibizumab Alone or in Combination with Calcium Dobesilate for the Treatment of Diabetic Macular Edema in Nonproliferative Diabetic Retinopathy Patients: 12-Month Outcomes of a Retrospective Study.

Objective: This study investigates the efficacy of CaD combined with intravitreal ranibizumab for the treatment of diabetic macular edema (DME) in patients with nonproliferative DR. Methods: This retrospective, observational, case-control study enrolled consecutive patients newly diagnosed with DME. The patients were treated with 3-monthly loading dose injections of intravitreal ranibizumab (IVR) followed by pro re nata injections (3 + PRN), with or without daily oral CaD. The patients were treated and followed up for 12 months. We reviewed their medical records to determine the optical coherence tomography (OCT) findings, number of injections, best-corrected visual acuity (BCVA), and central macular thickness (CMT) at 3, 6, and 12 months after the first injection. Results: We reviewed 102 eyes of 102 patients; 54 patients received IVR combined with oral CaD (IVR + CaD group) and 48 received only IVR (IVR group). In both groups, BCVA was higher, and CMT was lower, at 3, 6, and 12 months after the injection compared to those at the baseline (p < 0.05 for all), while there were no significant differences in BCVA improvement or CMT reduction between the two groups (p > 0.05). The mean number of IVR injections was significantly lower in the IVR + CaD group than the IVR group (5.4 ± 1.1 vs. 6.7 ± 1.6 injections, p < 0.05) during 1 year of treatment. No adverse events were noted in either group. Conclusions: Compared to IVR alone, the addition of oral CaD to IVR in DME patients was safe and effective for improving visual function and restoring the retinal anatomy and was associated with the need for fewer injections.

Evaluation of the therapeutic effects of calcium dobesilate in sciatic nerve crush injury in rats.

INTRODUCTION: Proinflammatory cytokines released from nerve endings and surrounding injured tissue after nerve damage can prolong the inflammation process, delay nerve healing or result in poor quality nerve healing. In this case, due to the loss of function in the muscles innervated by the damaged nerve, the patient may have neurological and functional difficulties which may reduce the patient's quality of life and create an economic burden. Although the attempts of many pharmacological agents to heal crush injury of peripheral nerves have been recorded in literature, a drug that can provide adequate recovery of the crushed nerve and can be applied in daily life has not been defined as yet. This study aimed to assess the effects of calcium dobesilate on sciatic nerve crush injury in a rat model. METHODS: A total of 26 male Wistar albino rats were separated into four groups as follows: CONTROL group (healthy subjects, n=6); SHAM group (crush injury was created, n=6); MP group (after created crush injury, methylprednisolone was administered, n=7); and CAD group (after created crush injury, calcium dobesilate was administered, n=7). A crush injury was created, then the electrophysiological findings and sciatic nerve functional index (SFI) were recorded before euthanasia. After the euthanasia of all the rats, samples of the crushed nerve and gastrocnemius muscle were evaluated histopathologically, immunohistochemically, and biochemically. RESULTS: Both pharmacological agents were histopathologically effective in axon regeneration and repair. Calcium dobesilate did not preserve total muscle mass but was seen to prevent atrophy microscopically. Immunohistochemistry and biochemistry results showed that calcium dobesilate and methylprednisolone had anti-inflammatory, anti-oxidant, anti-apoptotic, and anti-autophagic activity in the crushed sciatic nerve. Neither calcium dobesilate nor methylprednisolone improved the nerve conductance level. SFI values obtained on day 30 from the CAD group were numerically closer to the values of the healthy animals but not at a statistically significant level. CONCLUSION: The study results demonstrated that calcium dobesilate could suppress inflammatory processes and provide histopathological and functional improvements in the injured nerve in rats. Therefore, further clinical studies are recommended to investigate in detail the therapeutic effects of calcium dobesilate on peripheral nerve crush injury.

Effect of Chinese Patent Medicines on Ocular Fundus Signs and Vision in Calcium Dobesilate-Treated Persons With Non-Proliferative Diabetic Retinopathy: A Systematic Review and Meta-Analysis.

Background: Diabetic retinopathy (DR), one of the commonest microvascular complications in diabetic patients, is featured by a series of fundus lesions. Conventional Western medicine therapies for DR are always with modest treatment outcome. This paper is to assess the ocular fundus signs, vision and safety of Chinese patent medicines (CPMs) as an add-on treatment for DR. Method: 7 electronic databases were searched to determine eligible trials. Randomized controlled trials (RCTs) of non-proliferative diabetic retinopathy (NPDR) in which the intervention group received CPMs combined with calcium dobesilate (CD), and the control group received only CD were included for analysis. Two reviewers extracted the data independently. Results expressing as mean differences (MD) and relative risks (RR) were analyzed with a fixed-effects or random-effects models. Results: 19 RCTs involved 1568 participants with 1622 eyes met our inclusion criteria. The results suggested that compared with CD alone, CPMs plus CD for NPDR was superior at reducing the microaneurysm volume (MD -3.37; 95% confidence interval [CI], -3.59 to -3.14), microaneurysm counts (MD -2.29; 95%CI -2.97 to -1.61), hemorrhage area (MD -0.79; 95%CI -0.83 to -0.75), and macular thickness (MD -59.72; 95%CI -63.24 to -56.20). Participants in CPMs plus CD group also achieved a better vision. No obvious adverse events occurred. Conclusion: CPMs as an add-on therapy for NPDR have additional benefits and be generally safe. This meta-analysis demonstrated that CPMs combined with CD could improve retinal microaneurysm, hemorrhage, macular thickness, visual acuity, fasting blood glucose (FBG), and glycosylated hemoglobin (HbAlc) compared with CD alone. Further studies are needed to provide more conclusive evidence. Systematic Review Registration: PROSPERO https://www.crd.york.ac.uk/prospero/, identifier CRD42021257999.

Protective Effect of Calcium Dobesilate on Induced AKI in Severely Burned Mice.

BACKGROUND: Early acute kidney injury (AKI) predicts a high mortality rate in severely burned patients. However, the pathophysiology of early AKI induced by severe burn has not been well-defined. This study was designed to examine the protective effects of calcium dobesilate (CaD) against severe burn-induced early AKI in mice and explore the mechanism. METHODS: The shaved backs of mice were immersed in 100°C water for 10 s to make severe burn (40% of the total body surface area). CD-57 male mice were randomly divided into sham, burn, burn + vehicle, and burn + CaD groups. Renal function, reactive oxygen species generation, tubular necrosis, and phosphorylation of mitogen-activated protein kinase, protein kinase B (Akt), and nuclear factor (NF)-κB were measured at 24 and 48 h after the burn. Renal histology, ELISA, qRT-PCR, and Western blotting were performed on the renal tissue of mice to examine the effects and mechanisms at 24 and 48 h after the burn. RESULTS: Tubular damage, cast formation, and elevations of serum creatinine, BUN, and renal tissue kidney injury molecule 1 levels were all observed in the burned mice, and these were all alleviated in the mice with CaD treatment. In addition, the levels of oxidation-reduction potential and malondialdehyde were decreased, while the activities of the endogenous antioxidative enzymes were increased in the kidney tissues from the mice after CaD treatment. Furthermore, the activities of Akt, p38, extracellular sign-regulated kinase, Jun N-terminal kinase, and NF-κB signaling were increased in the kidney of burned mice and normalized after CaD treatment. CONCLUSION: This study has established, for the first time, the protective effect of CaD against early AKI in severely burned mice. CaD may exert its protective effect through alleviating oxidative stress, apoptosis, and inflammation, as well as modulating some signaling pathways in the kidney.

Efficacy of calcium dobesilate in treating Chinese patients with mild-to-moderate non-proliferative diabetic retinopathy (CALM-DR): protocol for a single-blind, multicentre, 24-armed cluster-randomised, controlled trial.

INTRODUCTION: Calcium dobesilate (CaD) has been used in the treatment of diabetic retinopathy (DR) due to its potential in protecting against retinal vascular damage. However, there is limited evidence exploring its efficacy in combating DR progression. This study is aimed at evaluating whether CaD could prevent DR progression into an advanced stage among Chinese patients with mild-to-moderate non-proliferative DR (NPDR). METHODS AND ANALYSIS: This study is a single-blind, multicentre, cluster-randomised, controlled superiority trial. A total of 1272 patients with mild-to-moderate NPDR will be enrolled and randomly assigned at a 1:1 ratio into the control group (conventional treatment group) and the intervention group (conventional treatment plus CaD (500 mg three times per day) for 12 months). Patients will be followed at 1, 3, 6 and 12 months after randomisation and receiving treatments, with the severity of DR assessed by the Early Treatment Diabetic Retinopathy Study (ETDRS) scale. The primary endpoint is the progression of DR during follow-up, which is defined as an increase of two or more steps in the ETDRS scale. The secondary endpoints include the concomitant changes in visual acuity, presence, number, location and type of retinal lesions, and retinal blood vessel diameter as well as the arteriovenous ratio at different visits. ETHICS AND DISSEMINATION: Each local ethics committee (first Vote: Ethical Review Committees of Zhongda Hospital of Southeast University (2019ZDSYLL132-P01)) has approved the study. The results will be published in high impact peer-reviewed scientific journals aimed at the general reader. TRIAL REGISTRATION NUMBERS: NCT04283162.

Calcium dobesilate prevents cisplatin-induced nephrotoxicity by modulating oxidative and histopathological changes in mice.

Cisplatin is one of the synthetic cancer medicines with nephrotoxicity being one of its major side effects. Past research shows that calcium dobesilate (CaD), as a vascular protective agent in diabetic retinopathy, has antioxidant properties. Thus, this study aims to evaluate the protective effects of CaD in cisplatin-induced nephrotoxicity in mice. A many as 28 mice, in the present experimental research, were randomly distributed into four groups, including control, cisplatin (the intraperitoneal administration of 20 mg/kg cisplatin only on the first day of the experiment), cisplatin + CaD 50 (cisplatin with the oral administration of 50 mg/kg CaD), and cisplatin + CaD 100 (cisplatin with the oral administration of 100 mg/kg CaD). The treated groups received CaD by oral gavage for 4 constitutive days. On the fifth day, the mice were sacrificed, and some biochemical (serum levels of Cr and BUN, renal tissue levels of MDA, and renal activities of SOD and GPx) and pathological parameters were evaluated. Based on the results, there was a significant decrease in the renal SOD and GPx activities; in contrast, there was a significant increase in the BUN, Cr, and renal MDA levels following administering cisplatin. However, the CaD treatment (100 mg/kg) significantly attenuated these alterations. In addition, the kidney's histological examination of kidneys confirmed the nephroprotective effects of CaD. The findings proved the protective impact of CaD on cisplatin-induced nephrotoxicity by an improvement in the oxidative stress factors.

Phlebotonics for venous insufficiency.

BACKGROUND: Chronic venous insufficiency (CVI) is a condition in which veins are unable to transport blood unidirectionally towards the heart. CVI usually occurs in the lower limbs. It might result in considerable discomfort, with symptoms such as pain, itchiness and tiredness in the legs. Patients with CVI may also experience swelling and ulcers. Phlebotonics are a class of drugs often used to treat CVI. This is the second update of a review first published in 2005. OBJECTIVES: To assess the efficacy and safety of phlebotonics administered orally or topically for treatment of signs and symptoms of lower extremity CVI. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL databases and the World Health Organization International Clinical Trials Registry Platform and Clinicaltrials.gov trials register up to 12 November 2019. We searched the reference lists of the articles retrieved by electronic searches for additional citations. We also contacted authors of unpublished studies. SELECTION CRITERIA: We included randomised, double-blind, placebo-controlled trials (RCTs) assessing the efficacy of phlebotonics (rutosides, hidrosmine, diosmine, calcium dobesilate, chromocarbe, Centella asiatica, disodium flavodate, French maritime pine bark extract, grape seed extract and aminaftone) in patients with CVI at any stage of the disease. DATA COLLECTION AND ANALYSIS: Two review authors independently extracted data and assessed the quality of included RCTs. We estimated the effects of treatment by using risk ratios (RRs), mean differences (MDs) and standardized mean differences (SMDs), according to the outcome assessed. We calculated 95% confidence intervals (CIs) and percentage of heterogeneity (I2). Outcomes of interest were oedema, quality of life (QoL), assessment of CVI and adverse events. We used GRADE criteria to assess the certainty of the evidence. MAIN RESULTS: We identified three new studies for this update. In total, 69 RCTs of oral phlebotonics were included, but only 56 studies (7690 participants, mean age 50 years) provided quantifiable data for the efficacy analysis. These studies used different phlebotonics (28 on rutosides, 11 on hidrosmine and diosmine, 10 on calcium dobesilate, two on Centella asiatica, two on aminaftone, two on French maritime pine bark extract and one on grape seed extract). No studies evaluating topical phlebotonics, chromocarbe, naftazone or disodium flavodate fulfilled the inclusion criteria. Moderate-certainty evidence suggests that phlebotonics probably reduce oedema slightly in the lower legs, compared with placebo (RR 0.70, 95% CI 0.63 to 0.78; 13 studies; 1245 participants); and probably reduce ankle circumference (MD -4.27 mm, 95% CI -5.61 to -2.93 mm; 15 studies; 2010 participants). Moderate-certainty evidence shows that phlebotonics probably make little or no difference in QoL compared with placebo (SMD -0.06, 95% CI -0.22 to 0.10; five studies; 1639 participants); and similarly, may have little or no effect on ulcer healing (RR 0.94, 95% CI 0.79 to 1.13; six studies; 461 participants; low-certainty evidence). Thirty-seven studies reported on adverse events. Pooled data suggest that phlebotonics probably increase adverse events slightly, compared to placebo (RR 1.14, 95% CI 1.02 to 1.27; 37 studies; 5789 participants; moderate-certainty evidence). Gastrointestinal disorders were the most frequently reported adverse events. We downgraded our certainty in the evidence from 'high' to 'moderate' because of risk of bias concerns, and further to 'low' because of imprecision. AUTHORS' CONCLUSIONS: There is moderate-certainty evidence that phlebotonics probably reduce oedema slightly, compared to placebo; moderate-certainty evidence of little or no difference in QoL; and low-certainty evidence that these drugs do not influence ulcer healing. Moderate-certainty evidence suggests that phlebotonics are probably associated with a higher risk of adverse events than placebo. Studies included in this systematic review provided only short-term safety data; therefore, the medium- and long-term safety of phlebotonics could not be estimated. Findings for specific groups of phlebotonics are limited due to small study numbers and heterogeneous results. Additional high-quality RCTs focusing on clinically important outcomes are needed to improve the evidence base.

Investigation of the Mechanism Underlying Calcium Dobesilate-Mediated Improvement of Endothelial Dysfunction and Inflammation Caused by High Glucose.

BACKGROUND/AIMS: Diabetic kidney disease (DKD) is a leading cause of end-stage renal disease. Calcium dobesilate (CaD) is widely used to treat diabetic retinopathy. Recent studies have demonstrated that CaD exerts protective effects against diabetic nephropathy. The aim of this study was to elucidate the molecular and cellular mechanisms underlying the protective effects of CaD. METHODS: Human umbilical vein endothelial cells (HUVECs) were cultured with different D-glucose concentrations to determine the effects of high glucose on HUVEC gene expression. HUVECs were also incubated with CaD (25 µM, 50 µM, and 100 µM) for 3 days to determine the effects of CaD on HUVEC viability. db/db mice were treated with CaD. 2-[(Aminocarbonyl)amino]-5-(4-fluorophenyl)-3-thiophenecarboxamide (TPCA-1) blocked the nuclear factor-κB (NF-κB) pathway in HUVECs. A pentraxin 3 (PTX3) small interfering RNA (siRNA) intervention experiment was performed in the cells. An adenovirus-encapsulated PTX3 siRNA intervention experiment was performed in db/db mice. Western blot and real-time PCR analyses were used to detect PTX3, p-IKBa/IKBa (I-kappa-B-alpha), and p-eNOS/eNOS (endothelial nitric oxide synthase) expression in mice and HUVECs. Hematoxylin-eosin (HE) staining and periodic acid-Schiff (PAS) staining were used to observe renal tissue damage in mice. PTX3 expression was observed by immunohistochemical staining. RESULTS: CaD downregulated the expression of PTX3 and p-IKBa/IKBa and upregulated the expression of p-eNOS/eNOS in vitro. When TPCA-1 was used, high glucose induced high PTX3 expression, and the expression of p-eNOS/eNOS increased. After PTX3 gene silencing, the expression of p-eNOS/eNOS also increased. In vivo, CaD reduced the expression of PTX3 and p-IKBa/IKBa in the kidneys of db/db mice and increased the expression of p-eNOS/eNOS. After PTX3 gene silencing, the urine protein and renal function of db/db mice were ameliorated, the glomerular extracellular matrix was decreased, and the expression of p-eNOS/eNOS was increased. CONCLUSIONS: Our results suggested that CaD may inhibit the expression of PTX3 by altering the IKK/IKB/NF-κB pathway, thereby improving endothelial dysfunction in HUVECs. PTX3 may be a potential therapeutic target for DKD.

The Effect of Calcium Dobesilate on Liver Damage in Experimental Obstructive Jaundice.

Purpose/Aim of the study: Inflammation and oxidative stress are two significant factors affecting the degree of liver damage in obstructive jaundice. The aim of this study was to evaluate the effect of calcium dobesilate (CaDob), an effective antioxidant and anti-inflammatory drug, on damage to liver caused by experimental obstructive jaundice. MATERIALS AND METHODS: 30 rats in total were randomly placed into three groups, each group consisting of 10 rats. The sham group (Group 1) only received solely laparotomy. In the control group (Group 2), ligation was applied to the biliary tract and no treatment was implemented. In the CaDob group (Group 3), following ligation of the biliary tract, 100 mg/kg/day CaDob was implemented via an orogastric tube for a 10-day period. Liver tissue and blood samples were taken for histopathological and biochemical examination. RESULTS: The CaDob group had significantly lower test values for serum liver functions when compared to the control group. Statistically lower levels of tissue malondialdehyde (MDA) and fluorescent oxidation products (FOP) were detected in the CaDob group, and the CaDob group had significantly higher levels of sulfydryl (SH) than the control group. Histopathological scores in the CaDob group were found out to be statistically less than the scores the control group received (p < 0.05). CONCLUSIONS: CaDob treatment repaired the histpatological changes induced by bile duct ligation. The hepatoprotective effects of CaDob can be associated with its antioxidant properties of the drug.

Diabetic Nephropathy Can Be Treated with Calcium Dobesilate by Alleviating the Chronic Inflammatory State and Improving Endothelial Cell Function.

BACKGROUND/AIMS: Diabetic kidney disease (DKD) is a leading cause of end-stage renal disease. However, no effective treatments for this disease are available. Calcium dobesilate (CaD) is widely used to treat diabetic retinopathy. DKD and retinopathy often co-exist and have similar mechanisms of pathogenesis. The aim of the present study was to elucidate the safety and efficacy of CaD in the treatment of DKD. METHODS: In the prospective randomised controlled study, 100 DKD from Type 2 diabetes mellitus (DM) patients with a urinary albumin/ creatinine ratio (ACR) ≥30 mg/g and urinary protein level between 150 mg/24 h and 2 g/24 h with GFR> 90ml/min were enrolled. The patients were randomly divided into the treatment group (500 mg of CaD, administered orally, 3 times per day) and the control group. DKD patients were treated for 3 months. In the case control study, DM patients without proteinuria and healthy individuals were also enrolled. Clinical data and related biochemical parameters were collected. Endothelial function markers (VEGF, ET-1, eNOS, NO) and inflammatory markers (MCP-1, ICAM, PTX3) were detected by ELISA. RESULTS: In the prospective randomised controlled study, the 24 h urinary albumin and 24 h urinary protein levels significantly decreased after three months of treatment with CaD in the patients with DKD, but the cystatin C-based glomerular filtration rate (GFR) remained unchanged. In addition, the levels of inflammatory markers (PTX3, MCP-1, hsCRP, ICAM) and endothelial dysfunction markers (VEGF, ET-1) were significantly reduced compared to pre-treatment levels, NO was signifcantly increased post treatment. In the case control study, we found that PTX3, MCP-1, ICAM, VEGF and ET-1 levels were positively correlated with urinary albumin in DKD patients, while the NO level was negatively correlated. Logistic regression analysis showed that PTX3, NO and HbAlc were influential factors in DKD. After patients with DKD were treated with CaD for three months, the 24 h urinary albumin and 24 h urinary protein levels significantly decreased, but the cystatin C-based glomerular filtration rate (GFR) remained unchanged. In addition, the levels of inflammatory markers (PTX3, MCP-1, hsCRP, ICAM) and endothelial dysfunction markers (VEGF, NO, ET-1) were significantly reduced compared to pre-treatment levels. CONCLUSION: CaD can be safely and effectively used to treatdiabetic nephropathy.

Effects of alprostadil combined with calcium dobesilate in patients with diabetic peripheral neuropathy.

OBJECTIVE: To observe the clinical curative effects of alprostadil combined with calcium dobesilate in type 2 diabetes patients with peripheral neuropathy. METHODS: We randomly divided 120 type 2 diabetes patients with diabetic peripheral neuropathy into two groups. The treatment group was prescribed alprostadil (10 µg, once daily) and oral calcium dobesilate (0.5 g, 3 times daily), and the control group was prescribed alprostadil (10 µg, once daily) for a total treatment duration of 2 weeks. The Michigan Diabetic Neuropathy Score (MDNS) and the Michigan Neuropathy Screening Instrument (MNSI) were used to evaluate differences between the two groups before and after treatment. RESULTS: Following 2 weeks of treatment, the total effective rate in the treatment group was significantly better than that of the control group (p<0.05) and the MDNS and MNSI scores in the treatment group were significantly lower than those in the control group (p<0.05 or p<0.01). CONCLUSION: Combined alprostadil and calcium dobesilate treatment for type 2 diabetic peripheral neuropathy showed good clinical efficacy and an improved curative effect than single alprostadil treatment.

Calcium dobesilate: A drug treatment for diabetic retinopathy can negatively interfere with the measurement of glycated albumin using the enzymatic method.

BACKGROUND: We reported that calcium dobesilate, a vasoprotective agent mainly used for diabetic retinopathy (DR), negatively interferes with glycated albumin (GA) assays involving enzymatic methods. METHODS: A calcium dobesilate standard was added to 3serum pools in vitro to prepare concentration-response series according to Clinical and Laboratory Standards Institute EP7-A2 guidelines. Percentage deviation between each drug concentration and the drug-free sample was calculated for 6 commercially available GA assays. The acceptable limit of deviation for GA was ±5.61%. For in vivo analyses, changes in serum concentrations of GA and calcium dobesilate were monitored in eight healthy participants before and after oral calcium dobesilate administration. RESULTS: At 16 µg/ml calcium dobesilate, within the therapeutic range, the percentage deviations for Asahi Kasei, Maccura, Leadman, Homa, and Medicalsystem assays were -8.7% to -49.7%, -2.0% to -47.7%, and -10.1% to -35.7% for low-, medium- and high-GA level interference pools, respectively, exhibiting dose-dependent negative interference. In vivo, calcium dobesilate ingestion was associated with statistically significant, falsely decreased measurements in 5 GA assays, 2 h after daily 500 mg administration. CONCLUSIONS: Calcium dobesilate ingestion was associated with erroneously low measurements in 5 GA assays. The degree of interference varied greatly among the assays examined.

Calcium dobesilate may alleviate diabetes­induced endothelial dysfunction and inflammation.

Diabetic kidney disease (DKD) is a leading cause of end­stage renal disease. However, the pathogenesis of DKD remains unclear, and no effective treatments for the disease are available. Thus, there is an urgent need to elucidate the pathogenic mechanisms of DKD and to develop more effective therapies for this disease. Human umbilical vein endothelial cells (HUVECs) were cultured using different D­glucose concentrations to determine the effect of high glucose (HG) on the cells. Alternatively, HUVECs were incubated with 100 µmol/l calcium dobesilate (CaD) to detect its effects. The authors subsequently measured HUVEC proliferation via cell counting kit­8 assays. In addition, HUVEC angiogenesis was investigated via migration assays and fluorescein isothiocyanate (FITC)­labelled bovine serum albumin (BSA) permeability assays. The content or distribution of markers of endothelial dysfunction [vascular endothelial growth factor (VEGF), VEGF receptor (R) and endocan) or inflammation [intercellular adhesion molecule (ICAM)­1, monocyte chemotactic protein (MCP)­1 and pentraxin­related protein (PTX3)] was evaluated via reverse transcription­quantitative polymerase chain reaction and western blotting. HG treatment induced increased in VEGF, VEGFR, endocan, ICAM­1, MCP­1 and PTX3 mRNA and protein expression in HUVECs. HG treatment for 24 to 48 h increased cell proliferation in a time­dependent manner, but the cell proliferation rate was decreased at 72 h of HG treatment. Conversely, CaD inhibited abnormal cell proliferation. HG treatment also significantly enhanced HVUEC migration compared to the control treatment. In contrast, CaD treatment partially inhibited HUVEC migration compared to HG exposure. HG­treated HUVECs exhibited increased FITC­BSA permeability compared to control cells cultured in medium alone; however, CaD application prevented the HG­induced increase in FITC­BSA permeability and suppressed HG­induced overexpression of endothelial markers (VEGF, VEGFR­2, endocan) and inflammation markers (ICAM­1, MCP­1, PTX3) in HUVECs. CaD has angioprotective properties and protects endothelial cells partly by ameliorating HG­induced inflammation. The current results demonstrated the potential applicability of CaD to the treatment of diabetic nephropathy, particularly during the early stages of this disease.

Molecular Mechanisms and Treatment Strategies in Diabetic Nephropathy: New Avenues for Calcium Dobesilate-Free Radical Scavenger and Growth Factor Inhibition.

Diabetic nephropathy is one of the most important microvascular complications of diabetes mellitus and is responsible for 40-50% of all cases of end stage renal disease. The therapeutic strategies in diabetic nephropathy need to be targeted towards the pathophysiology of the disease. The earlier these therapeutic strategies can bring about positive effects on vascular changes and prevent the vasculature in patients with diabetes from deteriorating, the better the renal function can be preserved. Studies evaluating anti-inflammatory and antioxidative strategies in diabetic nephropathy demonstrate the need and value of these novel treatment avenues. CaD is an established vasoactive and angioprotective drug that has shown a unique, multitarget mode of action in several experimental studies and in different animal models of diabetic microvascular complications. On the molecular level, CaD reduces oxidative stress and inhibits growth factors such as fibroblast growth factor and vascular endothelial growth factors. Recent findings have demonstrated a strong rationale for its use in reducing urine albumin excretion rate and markers of inflammation as well as improving endothelial function. Its beneficial effects make it an attractive therapeutic compound especially in the early stages of the disease. These findings, although promising, need further confirmation in prospective clinical trials with CaD.

Calcium dobesilate prevents the oxidative stress and inflammation induced by diabetes in the retina of db/db mice.

AIM: Calcium dobesilate (CaD) is beneficial in early stages of diabetic retinopathy (DR), but its mechanisms of action remains to be elucidated. The aim was to investigate the effect of CaD on proinflammatory cytokines and oxidative stress. METHODS: db/db mice were randomly assigned to daily oral treatment with CaD (200mg/kg/day) or vehicle for 15days. Biomarkers of oxidative stress (dihydroethidium, malondialdehyde), NF-κB, and proinflammatory cytokines (IL-1ß, IL-6, IL-8, TNF-α, MCP-1) were examined in the retina by immunohistochemical analysis. Cultures of human retinal endothelial cells (HRECs) were used for complementary experiments. RESULTS: CaD significantly reduced the biomarkers of oxidative stress in the retina of db/db mice. In addition, CaD prevented the increase of NF-κB, IL-6, IL-8, TNF-α and MCP-1 induced by diabetes. CaD inhibited the activation of NF-kß induced by IL-1ß by preventing IKKB-α phosphorylation in HRECs and reduced the upregulation of IL-6 and IL-18 induced by TNF-α in a dose-dependent manner. CONCLUSION: Our results suggest that antioxidant and antiinflammatory effects are crucial in accounting for the effectiveness of CaD for treating DR.

Calcium Dobesilate Prevents Diabetic Kidney Disease by Decreasing Bim and Inhibiting Apoptosis of Renal Proximal Tubular Epithelial Cells.

Apoptosis of renal proximal tubular epithelial cells (PTECs) plays a vital role in the pathogenesis and progression of diabetic kidney disease (DKD). Calcium dobesilate is a vascular protective compound used for treatment of diabetic retinopathy and chronic venous insufficiency. The aim of this study was to determine whether calcium dobesilate can protect PTECs from glucose-induced apoptosis and the potential mechanism of this effect. It is indicated that high glucose promoted abnormal apoptosis of HK2 cells, which was inhibited by treatment of calcium dobesilate, while Bim expression decreased in response to calcium dobesilate in high-glucose-treated HK2 cells. These findings confirmed the therapeutic effects of calcium dobesilate on DKD and emphasized the importance of it as a potentially crucial drug in treatment of DKD.

[Modern approach to early diagnosis and pathogenetic treatment of diabetic retinopathy]. / Sovremennye podkhody k rannei diagnostike, patogeneticheskomu lecheniyu diabeticheskoi retinopatii.

AIM: To improve the approach to pathogenetic treatment of diabetic retinopathy (DR) through early diagnosis and a new method for predicting disease progression. MATERIAL AND METHODS: The study enrolled 330 type 2 diabetes patients with DR (660 eyes), of whom women constituted 64.6%, men - 35.4%. The mean patient age was 62.3±2.3 years. Three groups were formed: the controls - 30 healthy volunteers (60 eyes) and 30 type 2 diabetes patients without ocular involvement (DR 0, 60 eyes); group 1 - 30 type 2 diabetes patients with DR I but no diabetic macular edema (DR I without DME, 60 eyes) that were treated with calcium dobesilate; group 2 - 240 type 2 diabetes patients, who had diabetic retinopathy of different stages (DR I, II, or III with DME, 480 eyes) and received laser retinal photocoagulation (LRP). The groups were all alike in terms of sex and age distribution. All patients underwent ophthalmic examination, including best corrected visual acuity (BCVA) and critical flicker fusion frequency (CFFF) testing, tonometry, biomicroscopy, MAIA fundus microperimetry, optical coherence tomography (OCT), and fluorescein angiography (FAG) of the retina. Traditionally we also determined blood sugar and glycated hemoglobin levels as well as vascular endothelial growth factor (VEGF-A) and monocyte chemoattractant protein (MCP-1) in tear fluid by ELISA. RESULTS: In group 1, which was under conservative therapy with calcium dobesilate, there was an increase in BCVA by the average of 0.95±0.02 and CFFF by 42.5±0.2 Hz (p<0,05). The mean central retinal thickness decreased reliably down to 265.1±12.1 µm (p<0.05). Light sensitivity of the macula improved and scored 24.13±12.3 dB (p<0.05). In group 2, the mean central retinal thickness appeared to be 383.1±221 µm, which was reliably higher than that in healthy individuals (p<0.05) and in type 2 diabetes patients without diabetic retinopathy (DR 0) (p<0.05). Tear assessment 12 months after the treatment revealed a significant decrease in VEGF-A and MCP-1 concentrations - down to 655.1±86.1 pg/ml and 1133 pg/ml, respectively (p<0.05). CONCLUSION: Conservative treatment with calcium dobesilate has proved effective in patients with DR I without DME as it ensures improvement and stabilization of the state of the retina (clinical and morphological) in one month already (judging from FAG and OCT findings). Laser treatment is rational in DR I, DR II, and DR III patients, whose condition is complicated with DME. Improvement and stabilization take, however, longer to be achieved - up to 1 year (according to FAG and OCT). Tear fluid assessment for particular participants in disease pathogenesis, such as VEGF-A and MCP-1, is a unique method for disease control and patient follow-up with account to different treatments. A new method for predicting the progression of diabetic retinopathy and diabetic macular edema has been suggested (RF patent for invention №2520826).