Comparing the effect of benzalkonium chloride-preserved, polyquad-preserved, and preservative-free prostaglandin analogue eye drops on cultured human conjunctival goblet cells.

PURPOSE: To investigate the effect of benzalkonium chloride (BAK)-preserved latanoprost and bimatoprost, polyquad (PQ)-preserved travoprost, and preservative-free (PF) latanoprost and tafluprost, all prostaglandin analogues (PGAs), on human conjunctival goblet cell (GC) survival. Furthermore, to investigate the effect of BAK-preserved and PF latanoprost on the cytokine secretion from GC. METHODS: Primary human conjunctival GCs were cultivated from donor tissue. Lactate dehydrogenase (LDH) and tetrazolium dye colorimetric (MTT) assays were used for the assessment of GC survival. A cytometric bead array was employed for measuring secretion of interleukin (IL)-6 and IL-8 from GC. RESULTS: BAK-preserved latanoprost and bimatoprost reduced cell survival by 28% (p = 0.0133) and 20% (p = 0.0208), respectively, in the LDH assay compared to a negative control. BAK-preserved latanoprost reduced cell proliferation by 54% (p = 0.003), BAK-preserved bimatoprost by 45% (p = 0.006), PQ-preserved travoprost by 16% (p = 0.0041), and PF latanoprost by 19% (p = 0.0001), in the MTT assay compared to a negative control. Only PF tafluprost did not affect the GCs in either assay. BAK-preserved latanoprost caused an increase in the secretion of pro-inflammatory IL-6 and IL-8 (p = 0.0001 and p = 0.0019, respectively) compared to a negative control, which PF latanoprost did not. CONCLUSION: BAK-preserved PGA eye drops were more cytotoxic to GCs than PQ-preserved and PF PGA eye drops. BAK-preserved latanoprost induced an inflammatory response in GC. Treatment with PF and PQ-preserved PGA eye drops could mean better tolerability and adherence in glaucoma patients compared to treatment with BAK-preserved PGA eye drops.

Preparation and performance of latanoprost-loaded hydrogels as a lacrimal suppository for the treatment of glaucoma.

Glaucoma is the leading cause of irreversible blindness, and its treatment is attracting widespread attention. Drug-loaded lacrimal suppositories can effectively treat xerophthalmia, but there is little research on the treatment of glaucoma with drug-loaded lacrimal suppositories. This article explored and expanded the non-pharmacological model of lacrimal suppository therapy for glaucoma by using a combination of lacrimal suppository and medication. The drug-loaded lacrimal suppository was rationally designed through the conjugation of gelatin with polyamide (PAM) via the formation of amide linkages, followed by Schiff base reaction grafting with latanoprost. In vitro drug release studies showed that latanoprost released from drug-loaded lacrimal embolus had sustained-release properties with a release time of 33 days and a drug release volume of 82.6%. The biological evaluation of drug-loaded lacrimal thrombus was carried out by IOP test, retinal potential test, and retinal H&E staining. The results showed that the IOP decreased to 27.125 ± 1.1254 mmHg, and the a and b waves of retinal potential increased to 4.39 ± 0.16 µV and 67.9 ± 2.17 µV, respectively. It indicated that latanoprost lacrimal suppository has a good therapeutic effect on glaucoma.

[Neuroprotective properties of latanoprost]. / Neiroprotektornye svoistva latanoprosta.

Glaucoma is the main cause of irreversible blindness in the world. Latanoprost - an ester prodrug of prostaglandin F2α (PGF2α) - was the first prostaglandin analogue used to treat glaucoma. The review shows that latanoprost possesses direct neuroprotective properties such as blocking the entry of calcium ions into neurons and inhibiting the action of caspase-3, inhibiting the activity of cyclooxygenase and activation of polypeptide 2B1 (OATP2B1) and Klotho protein. It is emphasized that when the drug is instilled into the eye, the concentration of the drug inside the vitreous body is twice as high as what is required to ensure the survival of retinal ganglion cells.

Comparative effects of latanoprost and latanoprostene bunod on intraocular pressure and pupil size in ophthalmologically normal Beagle dogs.

OBJECTIVE: To compare effects of latanoprost, a topical prostaglandin analogue (PGA) commonly used to treat glaucoma and lens instability in dogs, and latanoprostene bunod, a novel PGA with a nitric oxide-donating moiety, on intraocular pressure (IOP) and pupil diameter (PD). ANIMALS STUDIED: Ten ophthalmologically normal Beagle dogs. PROCEDURES: Dogs were treated twice a day for 5 days in a randomly selected eye with either latanoprost or latanoprostene bunod. After a 6-week washout period, dogs were treated with the opposite drug. IOP and PD were measured at treatment times, at midday on days 1 and 5, and for 6 days post-treatment. RESULTS: Both drugs significantly decreased IOP and PD. At midday on day 5 of treatment, mean IOP in eyes treated with latanoprost was 4.5 mmHg lower than the fellow eye and 3.0 mmHg lower than the same eye at baseline, while mean IOP in eyes treated with latanoprostene bunod was 5.5 mmHg lower than the fellow eye and 3.6 mmHg lower than baseline. Mean PD was 0.94 mm in eyes treated with latanoprost and 0.76 mmHg in eyes treated with latanoprostene bunod. There was no significant difference between the two drugs for either parameter at that time point (p = .372 and .619, respectively, for IOP relative to control and to baseline; p = .076 for PD) or when analyzed longitudinally. Significant diurnal variation in PD was noted and may have implications for treatment of lens' instability. CONCLUSIONS: Latanoprost and latanoprostene bunod produce similar IOP reduction and miosis in normal canine eyes.

Effect of travoprost, latanoprost and bimatoprost PGF2α treatments on the biomechanical properties of in-vivo rabbit cornea.

Prostaglandin F2α analogues (PGF2α), one of the most commonly prescribed classes of hypotensive agents, could decrease collagen fibril density and remodel the extracellular matrix in cornea. We hypothesized that PGF2α's would induce corneal softening, reduce the accuracy of intraocular pressure (IOP) measurement and lead to uncertainty in the effectiveness of the therapy. We determined the stress-strain behavior of rabbit cornea after PGF2α usage and evaluated the effect of biomechanical changes associated with PGF2α treatment on IOP measurements by Goldmann Applanation Tonometry (GAT). The tangent modulus decreased after PGF2α treatment, while the stromal interfibrillar spacing increased. PGF2α was shown to also affect the lateral eye with lower effect, which did not undergo direct eyedrop treatment. Significant decreases in the numerical predictions of GAT-IOP were predicted in all treated groups relative to control groups. Different PGF2α's (travoprost, latanoprost and bimatoprost) were associated with different extents of reduction in tissue stiffness and changes in corneal microstructure. PGF2α-induced changes in corneal mechanical properties could reduce the accuracy of IOP measurement and may cause an overestimation of the effect of PGF2α in lowering IOP, possibly leading to uncertainties in glaucoma management.

Puberty attainment and reproductive performance of yearling Bos indicus-influenced heifers after two sequential treatments with progesterone.

Number of pubertal heifers at time of breeding season initiation is a primary determinant to pregnancy success during the breeding season. It was hypothesized that pre-breeding progesterone (P4) supplementation (induction) would increase the number of heifers pubertal at the time of imposing estrous synchronization treatment regimens and P/AI. Yearling, Bos indicus-influenced (n = 577) or Bos indicus (n = 174) heifers were or were not treated with P4 (CIDR and Non-CIDR, respectively) for 10 d starting on D-23 (D0 = TAI). Presence of a CL on D-33 or D-23 was considered to indicate heifers were pubertal. On D-13, there was a PGF analogue administered. On D-9, there was treatment with GnRH analogue, 6d-CIDR and PGF. There were inseminations based on estrus (D-2 to D0) or TAI on D0 for non-estrous animals. There were 5.2 % and 62.9 % purebred and crossbred heifers pubertal, respectively. Proportion of prepubertal crossbred than purebred heifers with CL on D-3 was greater as a result of imposing the pubertal induction regimen (P < 0.05 and P> 0.10, respectively). Regardless of puberty status, proportion of heifers in estrus prior to AI in the CIDR group was similar to the heifers of the Non-CIDR group for crossbreds and purebreds. Similarly, P/AI of CIDR group was similar to the Non-CIDR group for crossbreds and purebreds. In summary, imposing the pubertal induction regimen hastened attainment of puberty in yearling crossbred, but not purebred heifers. Puberty induction did not affect estrous response, neither fertility after imposing an estrous synchronization treatment regimen.

Protection of 6-OHDA neurotoxicity by PGF2α through FP-ERK-Nrf2 signaling in SH-SY5Y cells.

6-Hydroxydopamine (6-OHDA) is a neurotoxin that destroy dopaminergic neurons and widely used to establish animal models of Parkinson's disease. Prostaglandins (PGs) are involved in various cellular processes, including the damage and repair of neuronal cells. However, the function of PGF2α in neuronal cells remains unclear. In this study, we investigated the effects of PGF2α against 6-OHDA-mediated toxicity in human neuroblastoma SH-SY5Y cells and elucidated its underlying molecular mechanism. When the cells were treated with 6-OHDA (50 µM) for 6 h, the expression levels of PGF2α synthetic enzymes; cyclooxygenase-2 and aldo-keto reductase 1C3 as PGF2α synthase were enhanced in an incubation-time-dependent manner. In addition, the production of PGF2α was increased in 6-OHDA-treated cells. Fluprostenol, a PGF2α receptor (FP) agonist (500 nM), suppressed 6-OHDA-induced cell death by decreasing the production of reactive oxygen species (ROS) and increasing the expression of the anti-oxidant genes. These fluprostenol-mediated effects were inhibited by co-treatment with AL8810, an FP receptor antagonist (1 µM) or transfection with FP siRNA (20 nM). Moreover, 6-OHDA-induced phosphorylation of extracellular signal-regulated kinase (ERK), a member of the mitogen-activated protein kinase family, was inhibited by co-incubation with AL8810. Furthermore, fluprostenol itself enhanced ERK phosphorylation and further elevated the 6-OHDA-induced phosphorylation of ERK. In addition, 6-OHDA induced nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2), activating anti-oxidant gene expression, was repressed by co-culturing with AL8810. These results indicate that PGF2α suppressed 6-OHDA-induced neuronal cell death by enhancing anti-oxidant gene expression via the FP receptor-ERK-Nrf2 signaling. Thus, FP receptor is a potential target for inhibition of ROS-mediated neuronal cell death.

Contribution of FP receptors in M1 macrophage polarization via IL-10-regulated nuclear translocation of NF-κB p65.

Macrophages are the effector immune cells with plasticity to differentiate as M1 (classically activated) and M2 (alternatively activated) phenotypes. Prostaglandins (PGs) have various important roles and are involved in the regulation of macrophage activation. However, the role of PGF2α in macrophage activation remains unclear. We investigated the role of PGF2α receptor (FP)-mediated signaling in the M1 macrophage polarization using murine macrophage RAW264.7 cells. Stimulation with lipopolysaccharide (LPS) + interferon (IFN)-γ increased the mRNA expression of the M1 macrophage markers such as inducible nitric oxide synthase, tumor necrosis factor-α, and CD11c. Pre-treatment with AL8810, an FP receptor antagonist, further enhanced the expression of these genes. In contrast, treatment with fluprostenol, an FP receptor agonist, decreased the LPS + IFN-γ-induced expression of M1 markers. LPS-induced M1 macrophage polarization was dependent on the activation of NF-κB p65. Treatment with IκB kinase ß inhibitor reduced AL8810-induced mRNA expression of the M1 markers. Stimulation with LPS + IFN-γ increased the expression of IL-10. Pre-treatment with AL8810 lowered LPS + IFN-γ-induced IL-10 expression, and further enhanced LPS + IFN-γ-stimulated nuclear translocation of NF-κB p65. In contrast, co-treatment with IL-10 reversed AL8810-induced nuclear translocation of NF-κB p65. These results indicate that the FP receptor signaling was involved in the control of M1 polarization of macrophages via IL-10-regulated nuclear translocation of NF-κB p65.

Effects of the Selective EP2 Receptor Agonist Omidenepag on Adipocyte Differentiation in 3T3-L1 Cells.

Purpose: We aimed at comparing the effects of omidenepag (OMD) with those of prostaglandin F (FP) receptor agonists (FP agonists) on adipogenesis in mouse 3T3-L1 cells. Methods: To evaluate the agonistic activities of OMD against the mouse EP2 (mEP2) receptor, we determined cAMP contents in mEP2 receptor-expressing CHO cells by using radioimmunoassays. Overall, 3T3-L1 cells were cultured in differentiation medium for 10 days and adipocyte differentiation was assessed according to Oil Red O-stained cell areas. Changes in expression levels of the adipogenic transcription factors Pparg, Cebpa, and Cebpb were determined by using real-time polymerase chain reaction (PCR). OMD at 0.1, 1, 10, and 40 µmol/L, latanoprost free acid (LAT-A) at 0.1 µmol/L, or prostaglandin F2α (PGF2α), at 0.1 µmol/L were added to cell culture media during adipogenesis. Oil Red O-stained areas and expression patterns of transcription factor targets of OMD or FP agonists were compared with those of untreated controls. Results: The 50% effective concentration (EC50) of OMD against the mEP2 receptor was 3.9 nmol/L. Accumulations of Oil Red O-stained lipid droplets were observed inside control cells on day 10. LAT-A and PGF2α significantly inhibited the accumulation of lipid droplets; however, OMD had no effect on this process even at concentrations up to 40 µmol/L. LAT-A and PGF2α significantly suppressed Pparg, Cebpa, and Cebpb gene expression levels during adipocyte differentiation. Conversely, OMD had no obvious effects on the expression levels of these genes. Conclusions: A selective EP2 receptor agonist, OMD, did not affect the adipocyte differentiation in 3T3-L1 cells, whereas FP agonists significantly inhibited this process.

Prostaglandin FP receptor antagonists: discovery, pharmacological characterization and therapeutic utility.

In contrast to the availability of potent and selective antagonists of several prostaglandin receptor types (including DP1 , DP2 , EP and TP receptors), there has been a paucity of well-characterized, selective FP receptor antagonists. The earliest ones included dimethyl amide and dimethyl amine derivatives of PGF2α , but these have failed to gain prominence. The fluorinated PGF2α analogues, AL-8810 and AL-3138, were subsequently discovered as competitive and non-competitive FP receptor antagonists respectively. Non-prostanoid structures, such as the thiazolidinone AS604872, the D-amino acid-based oligopeptide PDC31 and its peptidomimic analogue PDC113.824 came next, but the latter two are allosteric inhibitors of FP receptor signalling. AL-8810 has a sub-micromolar in vitro potency and ≥2 log unit selectivity against most other PG receptors when tested in several cell- and tissue-based functional assays. Additionally, AL-8810 has demonstrated therapeutic efficacy as an FP receptor antagonist in animal models of stroke, traumatic brain injury, multiple sclerosis, allodynia and endometriosis. Consequently, it appears that AL-8810 has become the FP receptor antagonist of choice. LINKED ARTICLES: This article is part of a themed section on Eicosanoids 35 years from the 1982 Nobel: where are we now? To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.8/issuetoc.

PTGFR activation promotes the expression of PTGS-2 and growth factors via activation of the PKC signaling pathway in bovine endometrial epithelial cells.

The endometrium of domestic animals has a remarkable capacity to self-repair. Prostaglandin F2α (PGF2α) is one of the major prostaglandins secreted from the endometrium. The role of PGF2α in endometrial repair, however, is still unknown. In the present study, it was investigated whether prostaglandin F2α receptor (PTGFR) activation could induce expression of prostaglandin-endoperoxide synthase 2 (PTGS-2) and growth factors associated with endometrial repair via activation of protein kinase C (PKC) signaling in endometrial epithelial cells (bEECs) of cattle. Results of the present study indicated that the treatment with the PTGFR agonist, fluprostenol, resulted in an increase in abundance of proteins for PTGS-2, vascular endothelial growth factor (VEGF), connective tissue growth factor (CTGF), transforming growth factor beta 1 (TGF-ß1), and interleukin-8 (IL-8). The increased abundances of these proteins were suppressed by the treatment with the PTGFR antagonist, AL8810.Furthermore, fluprostenol treatment also induced PKC phosphorylation. Subsequently, treatment with AL8810 inhibited the fluprostenol-induced PKC phosphorylation. Additionally, treatment with the PKC inhibitor, chelerythrine, reduced the fluprostenol-induced increase in the relative abundance of VEGF, CTGF, TGF-ß1, and IL-8 mRNA in bEECs. Taken together, these results suggest that PTGFR activation may induce endometrial repair by upregulating PTGS-2 gene expression and stimulating VEGF, CTGF, TGF-ß1, and IL-8 gene expression via activation of the PKC signaling pathway.

Effect of Fluprostenol Isopropyl Ester and 15-Keto Fluprostenol on Eyelash Growth: A Clinical and Pharmacologic Study.

15-Keto fluprostenol isopropyl ester and 15-keto fluprostenol have demonstrated a stimulatory effect on the growth and thickening of the eyelashes without the disadvantages of the prostaglandin derivatives of the PGF2α group, which have a hydroxyl group at position 15 in their structure. The two 15-ketoderivatives have the same efficacy as the 15-hydroxyl derivatives in allowing the regrowth, lengthening, darkening, or thickening of the eyelashes, but without darkening the edge of the eyelid or coloring the iris, even temporarily.

Prostaglandin F2α Receptor Modulation Affects Eye Development in Guinea Pigs.

Retinal arachidonic acid (ARA) levels in form-deprived eyes decline in guinea pigs. As prostaglandin F2α (PGF2α) is an ARA metabolite and endogenous agonist of prostaglandin F receptor (FP), we have been suggested that down-regulation of PGF2α-FP receptor signalling pathway contributes to myopia onset. To test this hypothesis, this study determines whether: (i) retinal PGF2α levels decline during the development of form deprivation myopia (FDM) in guinea pigs; (ii) FP receptor agonism and antagonism alter emmetropization and myopia development. Pigmented guinea pigs were randomly assigned to normal vision and form-deprived groups. Ultraperformance liquid chromatography coupled with a mass spectrometer (UPLC-MS) measured retinal PGF2α levels 2 weeks after form deprivation (FD). The selective FP agonist, latanoprost acid (LAT) and its corresponding antagonist, AL8810, were peribulbarly injected into each group. An eccentric infrared photorefractor (EIR) monitored refraction. A-scan ultrasonography measured axial elongation (AL) and vitreous chamber depth (VCD). Tonometry measured the intraocular pressure (IOP). Retinal PGF2α levels declined in form-deprived eyes compared to those in normal eyes. Neither LAT nor AL8810 affected IOP with or without FD. On the other hand, after 4 weeks of daily 0.5 µg AL8810 treatment, a myopia of -1.99 ± 0.34 dioptre (D) developed, but LAT had no effect on emmetropization in a normal visual environment. Nevertheless, daily 30 µg LAT treatment for 4 weeks inhibited FDM development by 41% (vehicle control: -8.39 ± 0.45 D; LAT: -4.95 ± 0.39 D; two-way anova with repeated measures, p < 0.05). Down-regulation of PGF2α-FP receptor signalling pathway may contribute to myopia onset as retinal PGF2α declined in myopic eyes and antagonism of FP receptor by AL8810 induced a myopic shift in normal vision environment. Meanwhile, up-regulation of this pathway by LAT inhibited FDM development. However, the mechanism underlying LAT-induced FDM inhibition needs further clarification. This uncertainty exists because its inhibition of FDM suggests that LAT strengthens the scleral framework which reduces axial elongation. On the other hand, its IOP-lowering effect is attributed to thinning and weakening the scleral framework in glaucoma treatment.

Effect of consecutive re-synchronization protocols on pregnancy rate in buffalo (Bubalus bubalis) heifers out of the breeding season.

The combined effect of six consecutive timed artificial inseminations (TAIs) on pregnancy rates, following two different synchronization protocols on buffalo heifers, over a period of seven months typically characterized by low breeding performances, were investigated in this study. A total of 2189 TAIs were performed on 1463 buffalo heifers within a large buffalo farm in the south of Italy. Individual animals were allowed to undergo synchronization protocol (either a slightly modified Ovsynch or Progesterone treatment) and TAI until establishment of pregnancy or else for not more than six consecutive times. Semen of seven proven bulls was used throughout the study, which was carried out from March to September of the same year. Therefore, other than the effect given by consecutive TAIs over time, a monthly and a seasonal effect could also be tested, once the entire period was split into a Low Breeding Season (LBS) from March to June, and a Transition to Breeding Season (TBS) from July to September. From the data recorded in this study and the statistical analysis performed, it can be stated that the two protocols for the synchronization of ovulation were similar in efficiency in determining pregnancies with an overall fertility rate of 89.4% when the comparison was run both on a monthly basis or when months were grouped into two different seasons. In addition, an average of 1.83 AI/pregnancy was reported, slightly higher for the Ovsynch when compared to the Progesterone protocol: 1.91 vs 1.70, respectively. Finally, when considering the number of progressive synchronization treatments implemented over time as covariate, neither Ovsynch nor Progesterone treatment significantly affected pregnancy rates following the first of the six synchronization sessions. However, repeating the synchronization procedure, the progesterone based protocol resulted in significantly higher probability of success in terms of established pregnancies during the second and third re-synchronization sessions.

The prostaglandin E2 receptor PTGER2 and prostaglandin F2α receptor PTGFR mediate oviductal glycoprotein 1 expression in bovine oviductal epithelial cells.

Oviductal glycoprotein 1 (OVGP1), an oviductin, is involved in the maintenance of sperm viability and motility and contributes to sperm capacitation in the oviduct. In this study, the regulatory effects exerted by prostaglandin E2 (PGE2) and F2α (PGF2α) on OVGP1 expression via their corresponding receptors in bovine oviductal epithelial cells (BOECs) were investigated. BOECs were cultured in vitro, and their expression of receptors of PGE2 (PTGER1, PTGER2, PTGER3, and PTGER4) and PGF2α (PTGFR) was measured using RT-qPCR. Ca2+ concentration was determined with a fluorescence-based method and cAMP was quantified by enzyme-linked immunosorbent assays to verify activation of PTGER2 and PTGFR by their corresponding agonists in these cells. OVGP1 mRNA and protein expression was measured using RT-qPCR and western blotting, respectively, following PTGER2 and PTGFR agonist-induced activation. PTGER1, PTGER2, PTGER4, and PTGFR were found to be present in BOECs; however, PTGER3 expression was not detected. OVGP1 expression was significantly promoted by 10-6 M butaprost (a PTGER2 agonist) and decreased by 10-6 M fluprostenol (a PTGFR agonist). In addition, 3 µM H-89 (a PKA inhibitor) and 3 µM U0126 (an ERK inhibitor) effectively inhibited PGE2-induced upregulation of OVGP1, and 5 µM chelerythrine chloride (a PKC inhibitor) and 3 µM U0126 negated OVGP1 downregulation by PGF2α. In conclusion, this study demonstrates that OVGP1 expression in BOECs is enhanced by PGE2 via PTGER2-cAMP-PKA signaling, and reduced by PGF2α through the PTGFR-Ca2+-PKC pathway.

Beta2 adrenergic receptor silencing change intraocular pressure in New Zealand rabbits.

PURPOSE/AIM: Glaucoma consists of a group of progressive optic neuropathies that are characterized by degeneration of the optic nerve and irreversible visual filed loss. Elevated intraocular pressure is the only proven treatable risk factor and commercial products used for glaucoma treatment are focused in lowering intraocular pressure. These drugs can have various undesirable side effects and this invites to look for new strategies. The purpose of this work is to study the use of a siRNA (small interfering RNA) to selectively silence beta2 adrenergic receptors and to see whether it reduces IOP (intraocular pressure). MATERIAL AND METHODS: Topical instillation of beta2 adrenergic receptors small-interfering RNA (siRNA, 25-250µg) was applied and IOP was measured with a Tonopen XL up to 9 consecutive days. The effect of such siRNA was compared to commercial compounds such as Timoftlol, Trusopt and Xalatan, and it was also analyzed if some anatomical changes occurred by microscopy. RESULTS: siRNA designed for beta2 adrenergic receptor induced a reduction of intraocular pressure (IOP) of 30±5%, compared to a control (scrambled siRNA). The results in terms of IOP decrease were similar to that found with commercial compounds but a long-lasting hypotensive action was shown by beta2 adrenergic receptor siRNA treatment as compared to commercial drugs. No apparent side effects were observed in the ocular structures. CONCLUSION: The use of siRNA against the beta2 adrenergic receptors could provide an interesting therapeutic strategy for glaucoma treatment.

Mirtogenol® supplementation in association with dorzolamide-timolol or latanoprost improves the retinal microcirculation in asymptomatic patients with increased ocular pressure.

OBJECTIVE: Supplementation with Mirtogenol® improves the retinal microcirculation and reduces intraocular pressure (IOP) in ocular hypertension, when administrated either alone or in association with an ophthalmic solution (latanoprost). In this study, microcirculatory parameters (perfusion of the circle of Zinn-Haller and retinal circulation) and oxidative stress were tested to assess the effects of Mirtogenol® plus traditional antihypertensive drugs in patients with elevated IOP. PATIENTS AND METHODS: 88 otherwise healthy patients with increased IOP were followed-up in a supplement registry for 12 weeks. Three groups received; (a) dorzolamide-timolol plus Mirtogenol®; (b) latanoprost drops plus Mirtogenol® or (c) latanoprost only. Oral supplementation consisted of two tablets/day of Mirtogenol® (80 mg of bilberry extract, Mirtoselect® plus 40 mg of Pycnogenol®). IOP, retinal blood flow, perfusion of the circle of Zinn-Haller, and oxidative stress were measured during the registry period. RESULTS: The three study groups were comparable; IOP and ocular blood flow velocity at inclusion were also comparable. Over the study period the decrease in IOP and the improvements in retinal microcirculation were statistically significant for all management groups, with a marginally more evident benefit in Mirtogenol®+latanosprost-treated patients. At 12 weeks, the altered perfusion at the circle of Zinn-Haller was improved in all groups; patients using Mirtogenol® showed a better perfusional pattern compared with subjects using only latanoprost. A reduction in oxidative stress was observed in supplemented subjects at the end of the study period; no significant change was seen in non-supplemented patients. All managements were well-tolerated without side effects. CONCLUSIONS: Supplementation with Mirtogenol®, in addition to local ophthalmic treatments, is safe and may contribute as a supplementary management to reach a normal IOP and ocular microcirculatory parameters.

Stanniocalcin-1 Is an Ocular Hypotensive Agent and a Downstream Effector Molecule That Is Necessary for the Intraocular Pressure-Lowering Effects of Latanoprost.

Purpose: To identify downstream signaling molecules through which intraocular pressure (IOP) is lowered following treatment with the prostaglandin analog latanoprost. Methods: Total RNA and protein isolated from primary human Schlemm's canal cells (n = 3) treated with latanoprost (free acid; 100 nM) were processed for quantitative PCR and Western blot analysis. IOP was evaluated in stanniocalcin-1 (STC-1-/-) and wild-type mice following treatment with latanoprost or Rho kinase inhibitor Y27632. Human anterior segment pairs (n = 8) were treated with recombinant STC-1 (5, 50, or 500 ng/mL) and pressure was recorded using custom-designed software. The effect of recombinant STC-1 (0.5 mg/mL) on IOP was evaluated in wild-type mice. Tissue morphology was evaluated by light and transmission electron microscopy. Results: Increased STC-1 mRNA (4.0- to 25.2-fold) and protein expression (1.9- to 5.1-fold) was observed within 12 hours following latanoprost treatment. Latanoprost reduced IOP in wild-type mice (22.0% ± 1.9%), but had no effect on STC-1-/- mice (0.5% ± 0.7%). In contrast, Y27632 reduced IOP in both wild-type (12.5% ± 1.2%) and in STC-1-/- mice (13.1% ± 2.8%). Human anterior segments treated with STC-1 (500 ng/mL) showed an increase in outflow facility (0.15 ± 0.03 to 0.27 ± 0.09 µL/min/mm Hg) while no change was observed in paired vehicle-treated controls. Recombinant STC-1 reduced IOP in wild-type mice by 15.2% ± 3.0%. No observable morphologic changes were identified between treatment groups when evaluated by microscopy. Conclusions: Latanoprost-induced reduction of IOP is mediated through the downstream signaling molecule STC-1. When used by itself, STC-1 exhibits ocular hypotensive properties.

Long interval prostaglandin as an alternative to progesterone-eCG based protocols for timed AI in sheep.

To compare the reproductive performance after TAI in ewes synchronized with mid (12 or 13) or long (14-16 d) interval prostaglandin (PG) or progesterone plus eCG (P4-eCG) based protocols, 440 multiparous Corriedale ewes were synchronized with two PG injections administered 12-16 d apart (PG12, PG13, PG14, PG15 and PG16 respectively), or P4-eCG (MAP sponges 14 d and eCG). Cervical TAI (Day 0) was performed with fresh semen. It was evaluated the ovulated ewes (OE, %) and the ovulation rate (OR) on Day 8 by trans-rectal ultrasonography, the rate of non-return to service between Days 13 and 21 by painted rams, and the pregnancy rate, prolificacy and fecundity on Day 60 by trans-abdominal ultrasonography. No significant differences were found in OE among groups (P>0.05), but P4-eCG achieved higher OR (P<0.05) compared to PG protocols, without differences among them (P>0.05). Similar NRR-21, pregnancy and fecundity were observed among PG15 (64.3, 62.9 and 84.3), PG16 (59.7, 59.7 and 77.8) and P4-eCG (70.3, 66.2 and 95.9), but higher compared to PG12 (42.5, 39.7 and 52.1) and PG13 group (44.0, 40.0 and 48.0, respectively; P<0.05). PG14 achieved intermediate results compared to other groups. No differences were found in prolificacy among groups (P>0.05), except PG13 that was lower compared to P4-eCG (P<0.05). In conclusion, long interval between PG injections (15 or 16 d) determined better reproductive outcome that mid interval (12 or 13 d), equating the P4-eCG based protocol after cervical TAI with fresh semen during the breeding season in sheep.