Biodegradable Harmonophores for Targeted High-Resolution In Vivo Tumor Imaging

Optical imaging probes have played a major role in detecting and monitoring a variety of diseases. In particular, nonlinear optical imaging probes, such as second harmonic generating (SHG) nanoprobes, hold great promise as clinical contrast agents, as they can be imaged with little background signal and unmatched long-term photostability. As their chemical composition often includes transition metals, the use of inorganic SHG nanoprobes can raise long-term health concerns. Ideally, contrast agents for biomedical applications should be degraded in vivo without any long-term toxicological consequences to the organism. Here, we developed biodegradable harmonophores (bioharmonophores) that consist of polymer-encapsulated, self-assembling peptides that generate a strong SHG signal. When functionalized with tumor cell surface markers, these reporters can target single cancer cells with high detection sensitivity in zebrafish embryos in vivo. Thus, bioharmonophores will enable an innovative approach to cancer treatment using targeted high-resolution optical imaging for diagnostics and therapy.

Analysis of the Human Plasma Proteome Using Multi-Nanoparticle Protein Corona for Detection of Alzheimer's Disease

As the population affected by Alzheimer's disease (AD) grows, so does the need for a noninvasive and accurate diagnostic tool. Current research reveals that AD pathogenesis begins as early as decades before clinical symptoms. The unique properties of nanoparticles (NPs) may be exploited to develop noninvasive diagnostics for early detection of AD. After exposure of NPs to biological fluids, the NP surface is altered by an unbiased but selective and reproducible adsorption of biomolecules commonly referred to as the biomolecular corona or protein corona (PC). The discovery that the plasma proteome may be differentially altered during health and disease leads to the concept of disease-specific PCs. Herein, the disease-specific PCs formed around NPs in a multi-NPs platform are employed to successfully identify subtle changes in plasma protein patterns and detect AD (>92% specificity and ≈100% sensitivity). Similar discrimination power is achieved using banked plasma samples from a cohort of patients several years prior to their diagnosis with AD. With the nanoplatform's analytic ability to analyze pathological proteomic changes into a disease-specific identifier, this promising, noninvasive technology with implications for early detection and intervention could benefit not only patients with AD but other diseases as well.

Nanomedicine for safe healing of bone trauma: Opportunities and challenges

Historically, high-energy extremity injuries resulting in significant soft-tissue trauma and bone loss were often deemed unsalvageable and treated with primary amputation. With improved soft-tissue coverage and nerve repair techniques, these injuries now present new challenges in limb-salvage surgery. High-energy extremity trauma is pre-disposed to delayed or unpredictable bony healing and high rates of infection, depending on the integrity of the soft-tissue envelope. Furthermore, orthopedic trauma surgeons are often faced with the challenge of stabilizing and repairing large bony defects while promoting an optimal environment to prevent infection and aid bony healing. During the last decade, nanomedicine has demonstrated substantial potential in addressing the two major issues intrinsic to orthopedic traumas (i.e., high infection risk and low bony reconstruction) through combatting bacterial infection and accelerating/increasing the effectiveness of the bone-healing process. This review presents an overview and discusses recent challenges and opportunities to address major orthopedic trauma through nanomedical approaches.

Cellular uptake of nanoparticles: journey inside the cell

Nanoscale materials are increasingly found in consumer goods, electronics, and pharmaceuticals. While these particles interact with the body in myriad ways, their beneficial and/or deleterious effects ultimately arise from interactions at the cellular and subcellular level. Nanoparticles (NPs) can modulate cell fate, induce or prevent mutations, initiate cell-cell communication, and modulate cell structure in a manner dictated largely by phenomena at the nano-bio interface. Recent advances in chemical synthesis have yielded new nanoscale materials with precisely defined biochemical features, and emerging analytical techniques have shed light on nuanced and context-dependent nano-bio interactions within cells. In this review, we provide an objective and comprehensive account of our current understanding of the cellular uptake of NPs and the underlying parameters controlling the nano-cellular interactions, along with the available analytical techniques to follow and track these processes.

Osmotic pressure-dependent release profiles of payloads from nanocontainers by co-encapsulation of simple salts

The encapsulation of payloads in micro- to nano-scale capsules allows protection of the payload from the surrounding environment and control of its release profile. Herein, we program the release of hydrophilic payloads from nanocontainers by co-encapsulating simple inorganic salts for adjusting the osmotic pressure. The latter either leads to a burst release at high concentrations of co-encapsulated salts or a sustained release at lower concentrations. Osmotic pressure causes swelling of the nanocapsule's shell and therefore sustained release profiles can be adjusted by crosslinking it. The approach presented allows for programing the release of payloads by co-encapsulating inexpensive salts inside nanocontainers without the help of stimuli-responsive materials.

Qualitative sensing of mechanical damage by a fluorogenic “click” reaction

A simple and unique damage-sensing tool mediated by a Cu(i)-catalyzed [3+2] cycloaddition reaction is reported, where a fluorogenic “click”-reaction highlights physical damage by a strong fluorescence increase accompanied by in situ monitoring of localized self-healing.

A triblock terpolymer vs. blends of diblock copolymers for nanocapsules addressed by three independent stimuli

The chemical structure of triblock terpolymers is exploited to achieve polymer nanocapsules responsive to three different stimuli.

Determination of nanoparticles using UV-Vis spectra

Nanoparticles (NPs) are increasingly being used in different branches of science and in industrial applications; however, their rapid detection and characterization at low concentration levels have remained a challenge; more specifically, there is no single technique that can characterize the physicochemical properties of NPs (e.g. composition and size). In this work we have developed a colorimetric sensor array for defining the physicochemical properties of NPs in aqueous solution with ultra-low concentrations (e.g. 10(-7) g ml(-1) for gold NPs). Various NPs were readily identified using a standard chemometric approach (i.e. hierarchical clustering analysis), with no misclassifications over 400 trials.

Superparamagnetic iron oxide nanoparticles for delivery of therapeutic agents: opportunities and challenges

INTRODUCTION

Bearing in mind that many promising drug candidates have the problem of reaching their target site, the concept of advanced drug delivery can play a significant complementary role in shaping modern medicine. Among other nanoscale drug carriers, superparamagnetic iron oxide nanoparticles (SPIONs) have shown great potential in nanomedicine. The intrinsic properties of SPIONs, such as inherent magnetism, broad safety margin and the availability of methods for fabrication and surface engineering, pave the way for diverse biomedical applications. SPIONs can achieve the highest drug targeting efficiency among carriers, since an external magnetic field locally applied to the target organ enhances the accumulation of magnetic nanoparticles in the drug site of action. Moreover, theranostic multifunctional SPIONs make simultaneous delivery and imaging possible. In spite of these favorable qualities, there are some toxicological concerns, such as oxidative stress, unpredictable cellular responses and induction of signaling pathways, alteration in gene expression profiles and potential disturbance in iron homeostasis, that need to be carefully considered. Besides, the protein corona at the surface of the SPIONs may induce few shortcomings such as reduction of SPIONs targeting efficacy.

AREAS COVERED

In this review, we will present recent developments of SPIONs as theranostic agents. The article will further address some barriers on drug delivery using SPIONs.

EXPERT OPINION

One of the major success determinants in targeted in vivo drug delivery using SPIONs is the adequacy of magnetic gradient. This can be partially achieved by using superconducting magnets, local implantation of magnets and application of magnetic stents. Other issues that must be considered include the pharmacokinetics and in vivo fate of SPIONs, their biodegradability, biocompatibility, potential side effects and the crucial impact of protein corona on either drug release profile or mistargeting. Surface modification of SPIONs can open up the possibility of drug delivery to intracellular organelles, drug delivery across the blood-brain barrier, modifying metabolic diseases and a variety of other multimodal and/or theranostic applications.

Reduction of metabolic signs of acute stress in male mice by Papaver rhoaes hydro-alcoholic extract

In the present study, effects of hydro-alcoholic extract of Papaver rhoeas L. (Papaveraceae) on the metabolic changes induced by electro foot shock stress in male NMRI mice (25-30 g) has been investigated. The mice were received electric foot shock (40 mV) for 100 sec. Plasma corticosterone levels, food and water intake and delay to eating (Anorexia) were assessed 20 min later. Different doses of the plant extract (15, 30 and 60 mg kg(-1)), or saline (10 mL kg(-1)) was injected to the animals intraperitoneally 30 min before the stress. The control groups received saline (10 mL kg(-1)) or the extract (15, 30 and 60 mg kg(-1)) and 30 min later were exposed to the apparatus but did not received stress. Our results indicated that stress can increase plasma corticosterone level significantly and the extract can exacerbate the stress effect. However, stress could reduce food and water intake and increase delay to eating times which were inhibited by the extract pretreatment. The results indicate that administration of the extract of Papaver rhoeas can reduce the side effects of stress but increases plasma corticosterone level which may be due to its effects on the adrenal gland.

Comparison of health status and quality of life of related versus paid unrelated living kidney donors

The aim of this cross-sectional study was to assess the health status and quality of life (QOL) of paid unrelated versus related living kidney donors postdonation at Shiraz Transplant Center in Iran. We invited all donors (n = 580, 347 paid unrelated, 233 related) who underwent donor nephrectomy at our center from 2004 to 2010 to participate in a health survey and physical examination. Of 580 donors, 144 consented to participate; participation of paid unrelated donors was significantly lower than related (52/347 vs. 92/233; p < 0.001). Participants underwent a complete physical examination, QOL assessment (using a 36-item short form health survey [SF-36] questionnaire) and laboratory work-up. The paid unrelated donors compared with related donors were younger (34.2 ± 7.2 vs. 40.7 ± 9.7 years, p < 0.001), had shorter time since donation (2.9 ± 1.6 vs. 3.8 ± 2 years, p = 0.004), had higher estimated GFR (72.6 ± 22 vs. 63.8 ± 15.3 mL/min/1.73 m(2), p = 0.006) and had a higher percentage of patients with microalbuminuria (35% vs. 0%, p < 0.001). Additionally, general health and social functioning scores among paid unrelated donors were significantly lower (p < 0.001 and p = 0.02, respectively) than related donors. Other SF-36 scores, although lower in paid unrelated donors, did not reach statistical significance. Iranian paid unrelated donors have lower QOL and higher incidence of microalbuminuria compared with related donors.

Temperature: the "ignored" factor at the NanoBio interface

Upon incorporation of nanoparticles (NPs) into the body, they are exposed to biological fluids, and their interaction with the dissolved biomolecules leads to the formation of the so-called protein corona on the surface of the NPs. The composition of the corona plays a crucial role in the biological fate of the NPs. While the effects of various physicochemical parameters on the composition of the corona have been explored in depth, the role of temperature upon its formation has received much less attention. In this work, we have probed the effect of temperature on the protein composition on the surface of a set of NPs with various surface chemistries and electric charges. Our results indicate that the degree of protein coverage and the composition of the adsorbed proteins on the NPs' surface depend on the temperature at which the protein corona is formed. Also, the uptake of NPs is affected by the temperature. Temperature is, thus, an important parameter that needs to be carefully controlled in quantitative studies of bionano interactions.

Slight temperature changes affect protein affinity and cellular uptake/toxicity of nanoparticles

It is known that what the cell actually "sees" at the nanoscale is an outer shell formed of 'protein corona' on the surface of nanoparticles (NPs). The amount and composition of various proteins on the corona are strongly dependent on the biophysicochemical properties of NPs, which have been extensively studied. However, the effect of a small variation in temperature, due to the human circadian rhythm, on the composition of the protein corona and the affinity of various proteins to the surface of NPs, was ignored. Here, the effect of temperature on the composition of protein corona and the affinity of various proteins to the surface of NPs and, subsequently, cell responses to the protein coated NPs are probed. The results confirmed that cellular entrance, dispersion, and toxicity of NPs are strongly diverse with slight body temperature changes. This new finding can help scientists to maximise NP entrance to specific cells/organs with lower toxicity by adjusting the cellular/organ temperature.

Pyrolytic carbon coating for cytocompatibility of titanium oxide nanoparticles: a promising candidate for medical applications

Nanoparticles for biomedical use must be cytocompatible with the biological environment that they are exposed to. Current research has focused on the surface functionalization of nanoparticles by using proteins, polymers, thiols and other organic compounds. Here we show that inorganic nanoparticles such as titanium oxide can be coated by pyrolytic carbon (PyC) and that the coating has cytocompatible properties. Pyrolization and condensation of methane formed a thin layer of pyrolytic carbon on the titanium oxide core. The formation of the PyC shell retards coalescence and sintering of the ceramic phase. Our MTT assay shows that the PyC-coated particles are cytocompatible at employed doses.

Toxicity of nanomaterials

Nanoscience has matured significantly during the last decade as it has transitioned from bench top science to applied technology. Presently, nanomaterials are used in a wide variety of commercial products such as electronic components, sports equipment, sun creams and biomedical applications. There are few studies of the long-term consequences of nanoparticles on human health, but governmental agencies, including the United States National Institute for Occupational Safety and Health and Japan's Ministry of Health, have recently raised the question of whether seemingly innocuous materials such as carbon-based nanotubes should be treated with the same caution afforded known carcinogens such as asbestos. Since nanomaterials are increasing a part of everyday consumer products, manufacturing processes, and medical products, it is imperative that both workers and end-users be protected from inhalation of potentially toxic NPs. It also suggests that NPs may need to be sequestered into products so that the NPs are not released into the atmosphere during the product's life or during recycling. Further, non-inhalation routes of NP absorption, including dermal and medical injectables, must be studied in order to understand possible toxic effects. Fewer studies to date have addressed whether the body can eventually eliminate nanomaterials to prevent particle build-up in tissues or organs. This critical review discusses the biophysicochemical properties of various nanomaterials with emphasis on currently available toxicology data and methodologies for evaluating nanoparticle toxicity (286 references).

The effect of simvastatin on lowering panel reactive antibody titer in sensitized dialysis patients: a randomized placebo controlled clinical trial

BACKGROUND

Patients with panel reactive antibodies (PRA) have many difficulties to find a crossmatch-negative kidney for transplantation and are at a higher risk of post-transplantation rejection.

OBJECTIVE

To evaluate the effect of simvastatin on PRA and post-transplant outcome of these sensitized patients.

METHODS

82 patients with end-stage renal disease (ESRD) with a PRA ≥25% were evaluated. In a one-year follow-up, the patients were treated with simvastatin. These patients were compared with 82 matched controls receiving placebo tablets. At the end of the second and 12(th) month, PRA was rechecked in all patients. Those patients who underwent transplantation continued to take simvastatin six months after transplantation. Serum creatinine levels were checked at monthly intervals post-operation.

RESULTS

The mean±SD PRA level at the end of the second month was 36.63%±31.14% and 45.34%±24.36% in cases and controls, respectively (P=0.012). Seven patients in the case group and 10 in the control group were lost to follow-up. The remaining patients continued to take simvastatin for 12 month. The mean±SD PRA level at the end of the 12(th) month was 24.02%±31.04% in cases and 43.15%±26.56% in controls (P=0.001). 25 patients underwent renal transplantation and continued to receive simvastatin 6 months after transplantation. These patients were matched with 25 controls treating with placebo. The mean±SD creatinine level 6 months after kidney transplantation was 2.05±1.14 mg/dL and 3.15±1.09 mg/dL in cases and controls consecutively (P=0.02).

CONCLUSION

Simvastatin can be safely used to lower PRA and improve post-transplantation outcomes.

Are Large Nonfunctional Kidneys Risk Factors for Posttransplantation Urinary Tract Infection in Patients With End-Stage Renal Disease Due To Autosomal Dominant Polycystic Kidney Disease?

OBJECTIVES

The objective of this study was to evaluate the effect of bilateral nephrectomy on posttransplantation urinary tract infection (UTI) among patients with end-stage renal disease (ESRD) due to autosomal dominant polycystic kidney disease (ADPKD).

METHODS

In a retrospective case-control design, 62 patients with ESRD with ADPKD were divided into 2 groups: (A) 24 patients who underwent bilateral nephrectomies, and (B) 38 patients in whom bilateral nephrectomies had not been done. Pretransplantation and posttransplantation urine cultures were evaluated for UTI.

RESULTS

Sixty-two patients with ESRD with ADPKD were enrolled in this study. The average age was 42 years (range, 6-60 years). Forty patients (64.5%) were male and 22 (35.5%) were female. The mean duration of hemodialysis was 24 months (range, 2-120 months), which was the same for both groups. Bilateral nephrectomies were done for 24 participants (38.7%). There were 38 patients (61.3%) in group B who did not have the operation. UTI occurred in 23 patients (37.1%): 6 patients (25%) in group A and 17 patients (44.7%) in group B. The incidence of UTI was not statistically different between the 2 groups (P>.05). Furthermore, no relationship was found between age, gender, blood group, and UTI in patients with ADPKD (P>.05).

CONCLUSION

According to our study, the presence of large nonfunctional kidneys is not a risk factor for posttransplantation UTI in patients with ADPKD and ESRD.

Cytokine gene polymorphisms in renal transplant recipients

OBJECTIVE

Acute rejection remains an important cause of graft loss after renal transplantation, and cytokines are key mediators in the induction and effector phases of all immune and inflammatory responses. However, the influence of gene polymorphisms on the functional immune response of transplant recipient outcomes remains controversial.

MATERIALS AND METHODS

The amplification refractory mutation system polymerase chain reaction was used to detect the interleukin-10 (IL-10) (-1082 G/A), tumor necrosis factor-alpha (TNF-alpha) (-308 G/A), and interferon-gamma (IFN-gamma) (+874 T/A) single nucleotide polymorphisms in 100 of the first adult kidney recipients at our institution who were receiving cyclosporine-based immunosuppressive therapy. The diagnosis of acute rejection was based on clinical and histologic findings according to the Banff criteria.

RESULTS

The results of multivariate analyses showed no significant association between episodes of acute rejection and single nucleotide polymorphisms in IL- 10, TNF-alpha genes, or dinucleotide repeat polymorphisms in the IFN-gamma gene.

CONCLUSIONS

Our results demonstrate that cytokine gene polymorphisms did not influence the early outcome of kidney transplantation.

Association between cyclosporine concentration and genetic polymorphisms of CYP3A5 and MDR1 during the early stage after renal transplantation

OBJECTIVES

Cyclosporine (CsA) has a narrow therapeutic range, and its pharmacokinetic characteristics vary among individuals. It also is a substrate for cytochrome P450 (CYP) 3A and P-glycoprotein, the product of the multidrug resistance 1 (MDR1) and CYP3A5 genes. Some of the single nucleotide polymorphisms (SNPs) in these genes are associated with deficient protein expression and reduced in vivo activity. We postulated that in renal transplant recipients, these SNPs should be associated with interindividual variations in CsA pharmacokinetics.

MATERIALS AND METHODS

In 88 Iranian renal transplant patients receiving CsA, CYP3A5 and MDR1 genotypes were determined by polymerase chain reaction, followed by restriction fragment length polymorphism analysis. Whole blood trough CsA concentrations were measured by radioactive immunosorbent assay. The dose-adjusted concentration (ng/mL per mg/kg/d) was calculated at 1 day (+/-2 days), 7 days, and 1 month after transplantation.

RESULTS

The MDR-1 wild-type genotype (3435CC) was observed in 17 patients (19%), whereas 45 patients (51%) were heterozygous (3435CT), and 26 patients (30%) were homozygous (3435 TT) for the mutation. In the days immediately after transplantation, we found a correlation between the concentration/dose ratio and the exon 26 MDR single nucleotide polymorphisms (33.3+/-15.24 microg mg/L/kg in the CT group vs 44.1+/-28.4 microg mg/L/kg in the TT group, P=.019). This ratio was significantly higher in subjects homozygous for the mutation (3435TT). This significant difference was not seen 1 week or 1 month after transplantation. All patients had the CYP3A5*3/*3 genotype, so no differences among the CYP3A5*1/*3 genotypes were found.

CONCLUSIONS

MDR-1 (3435CC) polymorphisms are associated with CsA pharmacokinetics and dose requirements in the first few days after renal transplantation. Pharmacogenetic methods could be used to help select the initial dosage and individualize immunosuppressive therapy. According to our results, the major genotype of our recipients is CYP3A5*3/*3. According to the literature, the recommended starting dosage of CsA is 9-14 mg/kg/day; however, the Iranian population has a good response with lower dosages (3-5 mg/kg/day), which may be explained by genetic differences.

Long-Term Results of Renal Transplantation: A Single-Center Analysis of 1200 Transplants

The present study is a report of long-term results of the first 1200 operations from December 1988 to December 2003. Graft and patient survival rates in eligible cases were computed with Kaplan-Meier analysis. Recipients were 808 men, 392 women of mean age 33.6 +/- 12.5 years. Eighty six percent of cases used organs from living donors (40% related, 41% unrelated, and 5% spouses) and 14% from cadaveric source. The most common causes of end-stage renal disease were chronic glomerulonephritis (18.2%); reflux nephropathy (13.4%); and diabetic nephropathy (10.1%). Among 215 (17.9%) patients, 156 patients (13%) died in the posttransplant period. Most common causes of death were cardiovascular (28.3%), graft loss (20.7%), and infections (19.6%). The 1- and 3-year patient survival rates were 94% and 91.5%, and graft survival rates were 88% and 84%. Although the success rate of operations was not satisfactory at the beginning, the current data reflect a >90% survival rate comparable to the major centers in the world.

Outcome of Hepatitis B and C Virus Infection on Graft Function After Renal Transplantation

INTRODUCTION

Chronic liver disease resulting from hepatitis B virus (HBV) and hepatitis C virus (HCV) infections is still a major concern in kidney recipients. It is unclear whether HCV antibody status and markers of HBV infection are associated with renal dysfunction. Thus, we designed a study to investigate the incidence of HBV and HCV infection after renal transplantation and whether these infections alter graft function.

METHODS

Fifty-eight patients who underwent renal transplantation participated in the study. Serum creatinine and aminotransferase levels were measured with standard automated analyzers. Anti-HCV antibodies were detected with an enzyme immunoassay, and a reverse transcriptase-polymerase chain reaction (RT-PCR) technique was used to test for HCV-RNA. Serological markers for HBV (HBsAg and anti-HBc antibody) were detected by enzyme immunoassay. All samples from patients who were seropositive for HBsAg or anti-HBc antibody were PCR-tested for HBV-DNA. A serum sample collected from living donors was tested for anti-HCV antibodies and serological markers for HBV. Serum creatinine and aminotransferase levels were also measured in living donors.

RESULTS

Anti-HCV was not detected in serum samples of any cases before transplantation. However, 10 (17.2%) tested positive after transplantation. HCV-RNA was detected in 2 of the 10 patients (3.4% of all patients). None of the pretransplantation serum samples tested positive for HBsAg. However, anti-HBc antibody was identified in 8 (13.8%) of the 58 patients.. No HBV DNA was detected in serum samples of the patients with anti-HBc or HBsAg-positive. HBsAg was only detected in 1 (1.7%) recipient after transplantation. None of the 58 patients showed clinical signs or symptoms of renal dysfunction during the study period.

CONCLUSION

Our data suggest that, neither HBV nor HCV infection appears to cause or contribute to renal dysfunction in the early period (1 year) after renal transplantation. Nevertheless, a long-term consequence of chronic HBV or HCV liver disease or graft loss is not impossible in renal transplant recipients.

Effect of Body Mass Index at Time of Transplantation and Weight Gain After Transplantation on Allograft Function in Kidney Transplant Recipients in Shiraz

Chronic renal allograft dysfunction is the most common cause of graft loss, for which there are multiple risk factors, including obesity before transplantation, which is believed to lower long-term renal allograft survival. One hundred eighty-two kidney transplant recipients were studied. Body mass index (BMI) at the date of transplantation was calculated. BMI values were classified into 4 categories: (1) patients with BMI <20, (2) BMI between 20 and <25, (3) BMI between 25 and <30, and (4) BMI > or =30. The minimum follow-up period in this study was 3 years after transplantation. The link between categorized BMI and the presence of renal allograft dysfunction and mortality within 3 years posttransplantation was investigated using independent sample t test. BMI at the date of transplantation showed statistically significant association with presence of renal allograft dysfunction and mortality within 3 years posttransplantation (P = .008, P = .01, respectively). BMI at the date of transplantation has a strong association with outcomes after renal transplantation. The extremes of very high and very low BMI are important risk factors for chronic renal allograft dysfunction; therefore, weight adjustment before kidney transplantation can be useful in improving the function of a transplanted kidney and increasing patient's survival.

A randomized, double-blind, placebo-controlled trial of supplementary vitamins E, C and their combination for treatment of haemodialysis cramps

BACKGROUND

Muscle cramps that improve after carnitine or vitamin E therapies are common in haemodialysis (HD) patients. Because vitamin C participates in carnitine biosynthesis, and its levels are reduced in uraemia, subclinical vitamin C depletion may contribute to HD cramps. Our aim was to determine the effects of vitamins C, E and their combination on the frequency and intensity of HD cramps.

METHODS

In this placebo-controlled, double-blind study, 60 HD-patients were randomized into four therapeutic groups. Each group (n=15) received six identical capsules daily for 8 weeks, containing one of the following: vitamin E (400 mg), vitamin C (250 mg), their combination, or placebo.

RESULTS

The frequency and intensity of HD cramps decreased significantly in all three vitamin groups compared with the placebo group at the end of the trial, and compared with the pre-treatment values. At the end of the trial, vitamins E, C, their combination, and placebo produced cramp reductions of 54, 61, 97 and 7%, respectively. The percentage cramp reduction had no significant correlation with age, sex, aetiology of end-stage renal disease, serum electrolytes or HD duration, but showed a positive correlation (r=0.33, P=0.01) with the type of therapy. No vitamin-related adverse effects were encountered during the trial.

CONCLUSION

Short-term treatment with the combination of vitamins E and C is safe and effective in reducing HD cramps; however, its safety for prolonged therapy has yet to be evaluated in HD patients.