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1.
Eur J Neurosci ; 45(6): 785-796, 2017 03.
Article in English | MEDLINE | ID: mdl-27992085

ABSTRACT

Involuntary choreiform movements are clinical hallmark of Huntington's disease, an autosomal dominant neurodegenerative disorder caused by an increased number of CAG trinucleotide repeats in the huntingtin gene. Involuntary movements start with an impairment of facial muscles and then affect trunk and limbs muscles. Huntington's disease symptoms are caused by changes in cortex and striatum neurons induced by mutated huntingtin protein. However, little is known about the impact of this abnormal protein in spinal cord motoneurons that control movement. Therefore, in this study we evaluated abnormalities in the motor unit (spinal cervical motoneurons, motor axons, neuromuscular junctions and muscle) in a mouse model for Huntington's disease (BACHD). Using light, fluorescence, confocal, and electron microscopy, we showed significant changes such as muscle fibers atrophy, fragmentation of neuromuscular junctions, axonal alterations, and motoneurons death in BACHD mice. Noteworthy, the surviving motoneurons from BACHD spinal cords were smaller than WT. We suggest that this loss of larger putative motoneurons is accompanied by a decrease in the expression of fast glycolytic muscle fibers in this model for Huntington's disease. These observations show spinal cord motoneurons loss in BACHD that might help to understand neuromuscular changes in Huntington's disease.


Subject(s)
Huntington Disease/pathology , Motor Neurons/pathology , Muscular Atrophy/pathology , Animals , Cervical Vertebrae/pathology , Male , Mice , Muscle, Skeletal/pathology , Neuromuscular Junction/pathology , Spinal Cord/pathology
2.
Curr Drug Deliv ; 18(7): 1022-1026, 2021.
Article in English | MEDLINE | ID: mdl-33388018

ABSTRACT

INTRODUCTION: The most common treatment for Primary Open-Angle Glaucoma (POAG) is the daily use of eye drops. Sustained-release drug delivery systems have been developed to improve patient adherence by achieving prolonged therapeutic drug concentrations in ocular target tissues while limiting systemic exposure. The purpose of this study is to compare the efficacy and safety of bimatoprost inserts with bimatoprost eye drops in patients with POAG and Ocular Hypertension (OH). METHODS: We include OH and POAG patients aged between 40 and 75 years-old. Both OH and POAG patients had intraocular pressure (IOP) greater than 21 and ≤30 mmHg at 9:00 am without glaucoma medication and normal biomicroscopy. Five normal patients with IOP≤14 mmHg constitute the control group. A chitosan-based insert of bimatoprost was placed at the upper conjunctival fornix of the right eye. In the left eye, patients used one drop of LumiganTM daily at 10:00 pm. For statistical analysis, a two-way analysis of variance (ANOVA), Student t-test, and paired t-test is used. RESULTS: Sixteen POAG and 13 OH patients with a mean age of 61 years were assessed. In both eyes, IOP reduction was similar during three weeks of follow-up (19.5±2.2 mmHg and 16.9±3.1 mmHg), insert, and eye drop, respectively; P=0.165). The percentage of IOP reduction in the third week was 30% for insert and 35% for eye drops (P=0.165). No intolerance or discomfort with the insert was reported. Among the research participants, 58% preferred the use of the insert while 25% preferred eye drops, and 17% reported no preference. CONCLUSION: Bimatoprost-loaded inserts showed similar efficacy to daily bimatoprost eye drops during three weeks of follow up, without major side effects. This might suggest a possible change in the daily therapeutic regimen for the treatment of POAG and OH.


Subject(s)
Glaucoma, Open-Angle , Glaucoma , Ocular Hypertension , Adult , Aged , Amides , Antihypertensive Agents , Bimatoprost , Glaucoma, Open-Angle/drug therapy , Humans , Intraocular Pressure , Middle Aged , Ocular Hypertension/drug therapy , Ophthalmic Solutions
3.
Int J Pharm ; 570: 118662, 2019 Oct 30.
Article in English | MEDLINE | ID: mdl-31491481

ABSTRACT

Eye drops containing hydrophilic drugs are commonly used to reduce intraocular pressure (IOP) in glaucoma patients, but compliance to the treatement is commonly reduced by frequent dosing and eventual systemic side effects. Sustained-release drug delivery systems, such as ocular inserts, can reduce dosing, limit systemic exposure, reduce side effects, and, then, improve patient adherence to therapy. Here, we developed and evaluated chitosan/hydroxyethyl cellulose-based ocular inserts for sustained release of dorzolamide, a hydrophilic drug. Dorzolamide inserts (DI) were produced by solvent/casting method and characterized by various physicochemical techniques. Pharmacokinetics studies were performed using scintigraphic images and ex vivo biodistribution. The effectiveness of inserts was tested in glaucomatous rats. Characterization studies showed that the drug strongly interacted with the polymeric matrix, but in vitro results showed that DI took only 3 h to release 75% of dorzolamide entraped. However, scintigraphic images and ex vivo biodistribution studies revealed that more than 50% of 99mTc-dorzolamide remained in the eye after 18 h of DI administration, while only about 30% of the drug remained in the eye after drops instilation. DI exerted significant hypotensive effect for two weeks, after single administration, while IOP values remained high in placebo and untreated groups. Eye drops were effective only during the treatment period. Only DI treatment prevented retinal ganglion cells death. Altogether, these findings evidenced the potential application of polymeric-based inserts for sustained release of dorzolamide in glaucoma management.


Subject(s)
Cellulose/analogs & derivatives , Chitosan/chemistry , Delayed-Action Preparations/chemistry , Glaucoma/drug therapy , Sulfonamides/chemistry , Sulfonamides/pharmacology , Thiophenes/chemistry , Thiophenes/pharmacology , Animals , Cellulose/chemistry , Delayed-Action Preparations/metabolism , Drug Delivery Systems/methods , Eye/drug effects , Eye/metabolism , Glaucoma/metabolism , Intraocular Pressure/drug effects , Male , Ophthalmic Solutions/chemistry , Ophthalmic Solutions/metabolism , Ophthalmic Solutions/pharmacology , Polymers/chemistry , Rats , Rats, Wistar , Sulfonamides/metabolism , Thiophenes/metabolism , Tissue Distribution
4.
Anim Reprod Sci ; 101(1-2): 28-37, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17010540

ABSTRACT

Oviducts from 22 crossbred heifers were examined for the presence of nuclear estrogen (ERalpha) and progesterone (PR) receptors at different phases (estrus, metaestrus and diestrus) of naturally occurring estrous cycles and estrous cycles during which superovulation was induced. Receptors were detected by immunohistochemistry in the epithelial cells, connective tissue and muscular layer of oviductal infundibulum, ampulla, ampullary/isthmic transition and isthmus. Epithelial ERalpha was found along the entire oviduct regardless of the cycle phase and of the circulating concentrations of 17beta-estradiol (E(2)) and progesterone (P(4)). Epithelial PR was found mainly at the ampullary-isthmic transition and isthmus and more intensely at the estrus phase but their amount was not correlated with P(4) concentrations. ERalpha in the connective tissue was more abundant at the infundibulum and ampulla, regardless of the phase of the estrous cycle and of E(2) and P(4) circulating concentrations. PR in the connective tissue was found mostly at the ampulla, regardless of the estrous cycle phase but no correlations were found between amount and P(4) concentrations. ERalpha staining intensity in the muscular layer was similar at all phases of the estrous cycle and at all anatomical segments of the oviducts. However, PR staining was more intense at the isthmus during the metaestrus phase and it was negatively correlated with P(4) concentrations. In general, data from the present research suggest that P(4) exerts an inhibitory role upon ERalpha and PR. Also, no differences were found between animals subjected or not to superovulation.


Subject(s)
Cattle , Estrous Cycle/metabolism , Oviducts/metabolism , Receptors, Estrogen/metabolism , Receptors, Progesterone/metabolism , Superovulation/metabolism , Animals , Estradiol/blood , Estrous Cycle/blood , Female , Male , Pregnancy , Progesterone/blood , Superovulation/blood , Tissue Distribution
5.
PLoS One ; 10(7): e0133149, 2015.
Article in English | MEDLINE | ID: mdl-26204514

ABSTRACT

The aim of this study was to develop and evaluate the effects of chitosan inserts for sustained release of the angiotensin-converting enzyme 2 (ACE2) activator, diminazene aceturate (DIZE), in experimental glaucoma. Monolayer DIZE loaded inserts (D+I) were prepared and characterized through swelling, attenuated total reflectance Fourier transformed infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC) and in vitro drug release. Functionally, the effects of D+I were tested in glaucomatous rats. Glaucoma was induced by weekly injections of hyaluronic acid (HA) into the anterior chamber and intraocular pressure (IOP) measurements were performed. Retinal ganglion cells (RGC) and optic nerve head cupping were evaluated in histological sections. Biodistribution of the drug was accessed by scintigraphic images and ex vivo radiation counting. We found that DIZE increased the swelling index of the inserts. Also, it was molecularly dispersed and interspersed in the polymeric matrix as a freebase. DIZE did not lose its chemical integrity and activity when loaded in the inserts. The functional evaluation demonstrated that D+I decreased the IOP and maintained the IOP lowered for up to one month (last week: 11.0 ± 0.7 mmHg). This effect of D+I prevented the loss of RGC and degeneration of the optic nerve. No toxic effects in the eyes related to application of the inserts were observed. Moreover, biodistribution studies showed that D+I prolonged the retention of DIZE in the corneal site. We concluded that D+I provided sustained DIZE delivery in vivo, thereby evidencing the potential application of polymeric-based DIZE inserts for glaucoma management.


Subject(s)
Diminazene/analogs & derivatives , Eye Proteins/agonists , Glaucoma/drug therapy , Peptidyl-Dipeptidase A/drug effects , Administration, Ophthalmic , Angiotensin-Converting Enzyme 2 , Animals , Blood Pressure/drug effects , Calorimetry, Differential Scanning , Chitosan , Delayed-Action Preparations , Diminazene/administration & dosage , Diminazene/pharmacokinetics , Drug Evaluation, Preclinical , Enzyme Activation/drug effects , Glaucoma/chemically induced , Glaucoma/pathology , Hyaluronic Acid/toxicity , Intraocular Pressure/drug effects , Male , Microscopy, Electron, Scanning , Rats , Rats, Wistar , Spectroscopy, Fourier Transform Infrared , Tissue Distribution
7.
Rev. bras. ciênc. morfol ; 7/8(2/1): 3-12, jul.-jun. 1990/1991. ilus, tab
Article in Portuguese | LILACS | ID: lil-163762

ABSTRACT

Sao descritos os aspectos histológicos e a distribuiçao de glicogênio e mucossubstâncias na próstata e nos três pares de glândulas bulbo-uretrais (Cowper) de Marmosa cinerea, marsupial Didelphidae com ampla distribuiçao geográfica no Brasil. Os três segmentos prostáticos, cranial, médio e caudal, apresentam túbulos secretores disseminados na mucosa uretral e sao divididos em zonas externa, média e interna, de acordo com as características morfológicas e tintoriais do epitélio secretor. No segmento cranial, o epitélio secreta glicogênio e mucossubstâncias neutras. No segmento médio sao produzidas mucossubstâncias neutras e sialomucinas, sendo sugerido um mecanismo apócrino de secreçao neste segmento. O epitélio do segmento caudal produz glicogênio, mucossubstâncias neutras e proteínas. O par lateral de bulbo-uretrais é formado por túbulos secretores longos e ramificados, que produzem mucossubstâncias neutras. O par intermédio constitui-se de túbulo-ácinos revestidos por células com porçao apical expandida e que secretam mucossubstâncias neutras, sialomucinas e sulfomucinas. Os túbulo-ácinos do par medial sao tortuosos e suas células produzem mucossubstâncias neutras.


Subject(s)
Animals , Male , Bulbourethral Glands , Glycogen , Mucus/metabolism , Prostate , Bulbourethral Glands/cytology , Glycogen/chemistry , Marsupialia , Mucus/chemistry , Prostate/cytology
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