Pharmacological considerations for treating neuroinflammation with curcumin in Alzheimer's disease

Prof. Dr. Peter Riederer, the former Head of the Neurochemistry Department of the Psychiatry and Psychotherapy Clinic at the University of Würzburg (Germany), has been one of the pioneers of research into oxidative stress in Parkinson's and Alzheimer's disease (AD). This review will outline how his scientific contribution to the field has opened a new direction for AD treatment beyond "plaques and tangles". In the 1990s, Prof. Riederer was one of the first scientists who proposed oxidative stress and neuroinflammation as one of the major contributors to Alzheimer's disease, despite the overwhelming support for the "amyloid-only" hypothesis at the time, which postulated that the sole and only cause of AD is β-amyloid. His group also highlighted the role of advanced glycation end products, sugar and dicarbonyl-derived protein modifications, which crosslink proteins into insoluble aggregates and potent pro-inflammatory activators of microglia. For the treatment of chronic neuroinflammation, he and his group suggested that the most appropriate drug class would be cytokine-suppressive anti-inflammatory drugs (CSAIDs) which have a broader anti-inflammatory action range than conventional non-steroidal anti-inflammatory drugs. One of the most potent CSAIDs is curcumin, but it suffers from a variety of pharmacokinetic disadvantages including low bioavailability, which might have tainted many human clinical trials. Although a variety of oral formulations with increased bioavailability have been developed, curcumin's absorption after oral delivery is too low to reach therapeutic concentrations in the micromolar range in the systemic circulation and the brain. This review will conclude with evidence that rectally applied suppositories might be the best alternatives to oral medications, as this route will be able to evade first-pass metabolism in the liver and achieve high concentrations of curcumin in plasma and tissues, including the brain.

Rectal bioavailability of amoxicillin sodium in rabbits: Effects of suppository base and drug dose

In this paper, rectal absorption and tissue tolerance of amoxicillin sodium (AS) suppositories prepared in a hydrophilic base, polyethylene glycol (PEG) or lipophilic base, Suppocire® NA 15 (SNA 15), were investigated. Following in vitro characterization, including drug distribution in the suppository bases, drug-base interactions and drug release, pharmacokinetics were investigated in rabbits to determine absolute bioavailability (F) at two dose levels (100 mg and 200 mg). Both types of suppositories were found uniform in weight and content. Powder X-ray diffraction (XRD) and differential scanning calorimetry indicated that AS existed as solid dispersion or anhydrous crystalline dispersion in both suppositories at different ratios without changing melting points of the bases. This was supported by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy conjugated with energy dispersive X-ray (SEM/EDX). In dissolution medium, melting and spreading of SNA 15 and dissolution of PEG suppositories accounted for their different drug release kinetics and mean dissolution time (MDT). A rapid and complete amoxicillin absorption (F close to 100%) with a double peak pharmacokinetic profile was observed alongside minimal signs of tissue irritation in rabbits treated with SNA 15 suppositories at both dose levels. In contrast, the F of amoxicillin from PEG suppositories was 59%, increasing to 77.3% as AS dose doubled from 100 mg to 200 mg, reflected in the slower release predominately controlled by erosion of the base. An in vitro - in vivo correlation was observed (MDT vs F; p < 0.01). AS was stable in SNA 15 suppositories at least for three months at 20 ± 0.2 °C. This research highlighted the advantages of SNA 15 suppositories over the PEG suppositories in providing rapid and complete rectal absorption of AS and tissue compatibility.

A synchronous fluorescence spectrofluorometric method for the simultaneous determination of policresulen and cinchocaine hydrochloride in ointment and suppositories

For the treatment of internal and external hemorrhoids, policresulen (POL) and cinchocaine hydrochloride (CIN) are used in combination. Using a new, simple, fast, and economical first-derivative synchronous fluorescence spectroscopic process, both drugs were simultaneously determined and validated. At Δλ60 nm and with a scanning rate of 600 nm/min, methanol was used as the solvent for both products. In the concentration ranges of 5.0-21.0 μg mL^-1 and 0.5-6.0 μg mL^-1 for POL and CIN, the amplitude-concentration plots were rectilinear. The detection limits were found to be 0.770 μg mL^-1 and 0.118 μg mL^-1 and the quantitation limits for POL and CIN were 2.541 μg mL^-1 and 0.391 μg mL^-1. To evaluate all compounds in synthetic mixtures and medicinal dosage types, the proposed method has been successfully applied. These findings were in line with the results obtained using high-performance thin layer chromatography, the comparison process.

[A multicenter, randomized, open and positive parallel controlled clinical study of clotrimazole vaginal expansion suppository and vaginal tablet in the treatment of mild and moderate vulvovaginal candidiasis]

Objective: Using clotrimazole vaginal tablet as a positive control, to evaluate the results of clotrimazole vaginal expansion suppository in the treatment of mild and moderate vulvovaginal candidiasis in terms of efficacy, patient satisfaction, side effects, and recurrence rate. Methods: This study was jointly conducted by 5 hospitals from August 2017 to October 2018, patients with mild and moderate vulvovaginal candidiasis confirmed by fungal culture and symptoms scores were selected. They were randomized to experimental group and control group as 1∶1 ratio. In the experimental group (n=105), the subjects applied clotrimazole vaginal expansion suppository (150 mg) daily at night for 7 days. In the control group (n=106), the subjects used a single dose of clotrimazole vaginal tablet (500 mg). Follow-ups were performed at (8±3) and (30±5) days after the discontinuation of the drugs, respectively. The difference in clinical symptoms and signs scores was used to evaluate the improvement of clinical symptoms, and the patient's satisfaction and side effects were recorded. Results: At the first follow-up, the experimental group and control group were followed up by fungal culture on the cure rate [66.7% (70/105) versus 63.2% (67/106), P>0.05] and total effective rate [98.1% (103/105) versus 99.1% (105/106), P>0.05], the differences were not statistically significant. At the second follow-up, the recurrence rates of the experimental group and the control group were 5.7% (4/70) and 14.9% (10/67), respectively, with no significant difference (P>0.05). In the evaluation of patient satisfaction, the leakage of the drug in the experimental group was significantly better than that in the control group (P<0.01). The side effects mainly included vaginal stimulation, itching and burning sensation, and there was no statistical difference between the two groups (χ²=1.070, P=0.586). Conclusions: In the treatment of mild and moderate vulvovaginal candidiasis, clotrimazole vaginal expansion suppository is no less effective than clotrimazole vaginal tablet, and there is no significant difference in the recurrence rate between the two. In terms of patient satisfaction, clotrimazole vaginal expansion suppository is superior to clotrimazole vaginal tablet.

Formulation, Physiochemical, and Microbial Assay of Henna Oil Vaginal Suppository Formulated with Polyethylene Glycol Bases

Background:

Persian Medicine is one of the oldest and richest complementary and alternative options in the field of medicine and has a comprehensive medical system. Henna oil is recommended in Persian Medicine for the treatment of numerous women’s diseases such as cervicitis. To date, henna has been used for many medical purposes, including astringent, bleeding, cardioinhibitory, hypotension, and relaxation. Accordingly, the present study aimed to provide the formulation of a henna-oil-based vaginal suppository and examine its physicochemical and antimicrobial properties.

Methods:

The present study was approved and performed in accordance with the regulations of Research Council, Kerman University of Medical Sciences, Kerman, Iran, in July 2016. Different percentages of henna oil, glycerin, and gelatin, as well as henna oil and polyethylene glycol 400 and 4000, were mixed to achieve a formulation with proper appearance features and, particularly, without any oil leakage from the suppository surface. Uniformity of weight, uniformity of content, disintegration time, and dissolution test of the suppositories were evaluated. The growth-inhibiting activity of the suppositories and aqueous extract of henna was evaluated against bacteria, including the Gram-positive bacterium Gardnerella vaginalis, Neisseria gonorrhoeae, and group B streptococcus.

Results:

The formulations had a smooth appearance without any cracks or fractures. Disintegration times for glycero-gelatin and polyethylene glycol suppositories were 60 and 10 min, respectively. 40% of the drug was released from polyethylene glycol suppositories after 60 min, but glycero-gelatin suppositories had no release after three hours. Minimum inhibitory concentration (MIC) of suppositories and aqueous extract were 0.4 mg/mL and 0.01 mg/mL, respectively.

Conclusion:

Polyethylene glycol suppositories had acceptable physicochemical properties, and the henna extract and suppositories inhibited the three studied pathogens.

Nanoformulated Eudragit lopinavir and preliminary release of its loaded suppositories

The development of novel paediatrics formulations is critical towards achieving the UNAIDS 90-90-90 targets. According to the latest UNAIDS reports, the availability of antiretrovirals (ARVs) for children has increased significantly, from 49% in 2015 to 53% in 2017. However, this percentage is considerably lower than the 80% for pregnant women that are currently on treatment. Therefore, there is still an urgent need for an alternative child-friendly delivery system. Lopinavir (LPV) is a protease inhibitor first-line HIV treatment drugs but suffers from low aqueous solubility, bitter state, short half-life leading to a limited dissolution and variable bioavailability upon oral administration. This work focused on the fabrication and characterization of a delivery system entailing Eudragit RSPO-LPV nanoparticles loaded suppositories in two different bases to improve the bioavailability and overcome the problem encountered through oral administration emanating from poor solubility. The prepared nanoparticles by nanoprecipitation method were characterized and compounded into suppositories in fattibase and polyethylene glycol (PEG) bases using a melt fusion method. The suppositories were stored at 5 and 25 °C, and were sampled at 0, 4, 8, 12 weeks. The samples were assessed by particle size, entrapment efficiency (EE), zeta potential and polydispersity index (PDI) variations. The preliminary in vitro release studies were analysed by HPLC. The nanoparticles have an average particle size of 191 nm with spherical morphology, entrapment efficiency, polydispersity index and zeta potential of 79.0 ± 0.5%, 0.224, and 25.87 ± 0.41 mV respectively. The surface analysis of the nanoparticles with FTIR, SEM, PXRD and TGA indicated that the drug was truly encapsulated without any interaction. The in vitro release studies showed that a better release was observed in suppositories formulated with PEG than the fattibase by having higher drug concentration released. Hence, this rectal formulation might serve as an alternative for paediatric HIV treatment upon further investigation.

Recurrent Eosinophilic Pneumonia Associated with Mesalazine Suppository in a Patient with Ulcerative Colitis

Mesalazine suppositories are widely used to treat ulcerative colitis and have a guaranteed safety profile, but although rare, they can cause pulmonary toxicity. A 35-year-old woman with ulcerative colitis was diagnosed to have acute eosinophilic pneumonia after 29 days of oral mesalazine use and improved after mesalazine and corticosteroid were withdrawn. Reintroduction of mesalazine suppositories resulted in acute eosinophilic pneumonia recurrence after 28 days. Mesalazine re-administration (even via a different route) in patients with a history of mesalazine-induced eosinophilic pneumonia should be undertaken cautiously, because eosinophilic pneumonia may recurrence.

Therapeutic requirements in active ulcerative proctitis: A single-centre study

BACKGROUND

Ulcerative proctitis (UP) presents distinctive clinical characteristics, outcomes and therapeutic approaches as compared to left-sided and extensive ulcerative colitis (UC).

AIM

To describe the current therapeutic requirements and clinical outcomes in patients with active UP.

METHODS

Retrospective observational study conducted in a referral IBD centre. Patients with UP in follow-up between 1989 and 2014 were included. The clinical characteristics, as well as the different treatments and drug formulations administered to treat flares, were recorded.

RESULTS

Out of 687 UC patients, 101 patients (15%) with UP were included. Median follow-up was 8 years (IQR 3-14) and 49% of patients presented disease activity during the study period. Topical mesalazine monotherapy (90%) was the most commonly administered treatment for disease activity (mostly as suppositories), followed by topical steroids (47%) and oral mesalazine (56%) in monotherapy or combination therapy. Only 14% and 16% of patients required oral prednisone and beclomethasone, respectively.

CONCLUSIONS

In clinical practice, active UP presents mostly favourable outcomes. Mesalazine suppositories are by far the most used treatment for these patients.

Na2S, a fast-releasing H2S donor, given as suppository lowers blood pressure in rats

BACKGROUND

Hydrogen sulfide (H₂S) is involved in blood pressure control. The available slow-releasing H₂S-donors are poorly soluble in water and their ability to release H₂S in biologically relevant amounts under physiological conditions is questionable. Therefore, new slow-releasing donors or new experimental approaches to fast-releasing H₂S donors are needed.

METHODS

Hemodynamics and ECG were recorded in male, anesthetized Wistar Kyoto rats (WKY) and in Spontaneously hypertensive rats (SHR) at baseline and after: 1) intravenous (iv) infusion of vehicle or Na₂S; 2) administration of vehicle suppositories or Na₂S suppositories.

RESULTS

Intravenously administered vehicle and vehicle suppositories did not affect mean arterial blood pressure (MABP) and heart rate (HR). Na₂S administered iv caused a significant, but transient (2-5min) decrease in MABP. Na₂S suppositories produced a dose-dependent hypotensive response that lasted ∼45min in WKY and ∼75-80min in SHR. It was accompanied by a decrease in HR in WKY, and an increase in HR in SHR. Na₂S suppositories did not produce a significant change in corrected QT, an indicator of cardiotoxicity. Na₂S suppositories increased blood level of thiosulfates, products of H₂S oxidation.

CONCLUSIONS

Na₂S administered in suppositories exerts a prolonged hypotensive effect in rats, with no apparent cardiotoxic effect. SHR and WKY differ in hemodynamic response to the H₂S donor. Suppository formulation of fast-releasing H₂S donors may be useful in research, if a reference slow-releasing H₂S donor is not available.

Comparison of physicochemical properties of suppositories containing starch hydrolysates

The purpose of this work was to determine the effect of starch hydrolysates (SH) on the physicochemical properties of suppositories. The study was conducted with suppositories with acetaminophen (AAP) a typical antipyretic analgesic, as model drug on lipophilic (cocoa butter) and hydrophilic base (polyethylene glycol 1500 + 400). The suppositories with and without the addition of SH were examined for physicochemical tests according to European Pharmacopoeia 8th edition (Ph. Eur.): the uniformity of mass of single-dose preparation test, the softening time determination of lipophilic suppositories test, the disintegration of suppositories test, and dissolution test with flow-through apparatus. The results confirm the possibility of using starch hydrolysates as a cheap and safe addition to modify physicochemical properties of suppositories.

Enemas, suppositories and rectal stimulation are not effective in accelerating enteral feeding or meconium evacuation in low-birthweight infants: a systematic review

Early full enteral feeding in preterm infants decreases morbidity and mortality. Our systematic review covered the effectiveness of rectal stimulation, suppositories and enemas on stooling patterns and feeding tolerance in low-birthweight infants born at up to 32 weeks. It comprised seven studies published between 2007 and 2014 and covered 495 infants.

CONCLUSION

Suppositories were ineffective in shortening the time to reach full enteral feeding, and the evidence on enemas was contradictory. Enemas and rectal stimulation did not shorten the time until complete meconium evacuation was reached. Further research into safe, effective interventions to accelerate meconium excretion is needed.

Free fatty acid suppositories are as effective as docusate sodium and sorbitol enemas in treating constipation in children

AIM

A well-documented, clinically proven per rectum treatment for childhood constipation is needed. This phase two clinical trial evaluated the efficacy of suppositories containing free fatty acids (FFA) compared with Klyx docusate sodium and sorbitol enemas.

METHODS

A randomised, controlled, single-blind study was undertaken on 77 children aged between one and 17 who presented to an emergency department in Iceland and were diagnosed with constipation. In stage one, 23 patients were randomised to receive lower dose FFA suppositories or Klyx (n = 33). In stage two, 21 different patients were randomised to receive higher dose suppositories and compared with the same Klyx control subjects.

RESULTS

The suppositories were effective at bowel emptying in 39% of the group who received the lower FFA doses and 81% of the group receiving higher doses, compared with 88% in the Klyx control group. Symptom relief was obtained in 30% of the group receiving the lower doses and 71% of the group receiving the higher doses, compared with 73% in the control group.

CONCLUSION

The higher dose FFA suppositories were as effective as the Klyx enemas with regard to bowel emptying and symptom relief and might provide an important and less invasive alternative for childhood constipation.

Validated Stability-Indicating HPLC-DAD Method for the Simultaneous Determination of Diclofenac Sodium and Diflunisal in Their Combined Dosage Form

A simple, rapid, and highly selective HPLC-DAD method was developed for the simultaneous determination of diclofenac sodium (DIC) and diflunisal (DIF) in pure form and in their combined formulation. Effective chromatographic separation was achieved using a Zorbax SB-C8 (4.6×250 mm, 5 μm particle size) column with a mobile phase composed of 0.05 M phosphoric acid, acetonitrile, and methanol in the ratio of 40:48:12 (by volume). The mobile phase was pumped isocratically at a flow rate of 1 mL/min, and quantification of the analytes was based on measuring their peak areas at 228 nm. The retention times for diflunisal and diclofenac were about 7.9 and 9.5 min, respectively. The reliability and analytical performance of the proposed HPLC procedure were statistically validated with respect to system suitability, linearity, ranges, precision, accuracy, specificity, robustness, detection, and quantification limits. Calibration curves were linear in the ranges of 5–100 μg/mL for both drugs with correlation coefficients >0.9998. The proposed method proved to be selective and stability-indicating by the resolution of the two analytes from four of their related substances and potential impurities as well as from forced-degradation (hydrolysis, oxidation, photolysis, and dry heat) products. The validated HPLC method was successfully applied to the analysis of DIC and DIF in their combined dosage form (suppositories). The proposed method made use of the diode array detector (DAD) as a tool for peak identity and purity confirmation.

Effects of suppository acetaminophen, bupivacaine wound infiltration, and caudal block with bupivacaine on postoperative pain in pediatric inguinal herniorrhaphy

Background:

The control of postoperative pain is important in children, and poor pain control leads to organ dysfunction and behavioral problems.

Objectives:

We compared the analgesic effects of suppository acetaminophen, bupivacaine wound infiltration, and caudal block with bupivacaine on postoperative pain in pediatric inguinal herniorrhaphy.

Patients and Methods:

In this double-blinded, randomized controlled clinical trial, 90 children of American Society of Anesthesiologists (ASA) grade I-II, aged between 3 months and 7 years, and scheduled for elective unilateral inguinal herniorrhaphy under general anesthesia were assigned to three equal groups. Patients in the first group received 20 mg/kg of suppository acetaminophen. In the second group, 2 mg/kg of 0.5% bupivacaine was infiltrated in the incisional site, and in the third group, a caudal block was performed with 0.75 mL/kg of 0.25% bupivacaine. The Face, Legs, Activity, Cry, Consolability (FLACC) pain scale was applied 30 minutes after operation. Thereafter, the FLACC score was obtained every hour during the next 6 hours. If the FLACC score was 4 or over, we administered 0.5 mg/kg of intravenous meperidine. The data was transferred to SPSS-10 software and analyzed statistically with chi-square and analysis of variance tests. P < 0.05 was considered significant.

Results:

The mean analgesic duration in the acetaminophen, bupivacaine infiltration, and caudal block groups was 4.07, 5.40, and 5.37 hours, respectively. Significant differences were not observed between the bupivacaine infiltration and caudal block groups (P = 0.9), but the differences between the bupivacaine infiltration and acetaminophen groups (P = 0.034) and the caudal block and acetaminophen groups (P = 0.039) were significant. With regard to meperidine administration, significant differences were not observed between the bupivacaine infiltration and caudal block groups (P = 0.848), but significant differences were observed between these two groups and the acetaminophen group (P < 0.05).

Conclusions:

Patients in the bupivacaine infiltration and caudal block groups had less postoperative pain than those in the acetaminophen group and received lower amount of meperidine. We concluded that in children, bupivacaine infiltration and caudal block with bupivacaine produce better analgesia than suppository acetaminophen. It seems that bupivacaine infiltration is better than caudal block because of its simplicity, lower incidence of complications, and failure rate.