Effects of iota-carrageenan on ocular Chlamydia trachomatis infection in vitro and in vivo

Abstract

Ocular chlamydial infections with the ocular serovars A, B, Ba, and C of Chlamydia trachomatis represent the world’s leading cause of infectious blindness. Carrageenans are naturally occurring, sulfated polysaccharides generally considered safe for food and topical applications. Carrageenans can inhibit infection caused by a variety of viruses and bacteria. To investigate whether iota-carrageenan (I-C) isolated from the red alga Chondrus crispus could prevent ocular chlamydial infection, we assessed if targeted treatment of the conjunctival mucosa with I-C affects chlamydial attachment, entry, and replication in the host cell. Immortalized human conjunctival epithelial cells were treated with I-C prior to C. trachomatis infection and analyzed by flow cytometry and immunofluorescence microscopy. In vivo effects were evaluated in an ocular guinea pig inclusion conjunctivitis model. Ocular pathology was graded daily, and chlamydial clearance was investigated. Our study showed that I-C reduces the infectivity of C. trachomatis in vitro. In vivo results showed a slight reduced ocular pathology and significantly less shedding of infectious elementary bodies by infected animals. Our results indicate that I-C could be a promising agent to reduce the transmission of ocular chlamydial infection and opens perspectives to develop prophylactic approaches to block C. trachomatis entry into the host cell.

Carrageenan oligosaccharides and their degrading bacteria induce intestinal inflammation in germ-free mouse

“…Accumulating evidence indicates that κ-CGNs, especially their low-MW degradation products, induce inflammation in the colon, resulting in a range of diseases in cell and animal models, including thrombosis [28][29][30][31], peritonitis [26,[32][33][34], paw edema [35,36], pleurisy [37,38], gastroenterocolitis [39,40], arthritis [41,42], and inflammatory bowel disease. However, CGNs also show positive health effects, such as antitumor [43], antimicrobial [44], and antiviral [45,46]. Removal of sulfate esters from sulfated polysaccharides is considered one of the essential steps for microorganisms in the degradation of sulfurized polysaccharides [47].…”

The Evolution Road of Seaweed Aquaculture: Cultivation Technologies and the Industry 4.0

“…Carrageenans are utilized in the pharmaceutical industry [ 198 , 200 ], focusing on anti-inflammatory [ 201 ], antiviral [ 202 , 203 , 204 , 205 , 206 , 207 ], anticoagulant [ 208 , 209 ], immunomodulatory [ 210 ], antitumoral [ 211 ], antioxidant [ 208 , 211 , 212 ], anti-angiogenic [ 213 ] and neuroprotective [ 211 ] activities. The function of carrageenans in agriculture has been verified [ 214 , 215 , 216 , 217 , 218 , 219 , 220 , 221 ].…”

Carrageenan: Drug Delivery Systems and Other Biomedical Applications

“…In other research, Inic-Kanada and co-workers tested the effects of iota -CG on ocular Chlamydia trachomatis infection. Iota -CG tends to reduce the infectivity of Chlamydia trachomatis in vitro and when it was evaluated in vivo, the results showed slightly reduced ocular pathology and significantly less shedding of infectious elementary bodies, which suggested that iota -CG could be a promising agent for reduction of the transmission of ocular chlamydial infection, with more in-depth studies to support these first results [ 30 ].…”

“…CG has therefore become one of the main biomaterials for a range of purposes in the pharmaceutical industry, since they have been used to improve the formulation of medications and the controlled release of drugs [ 20 , 21 , 22 ]. CG has also revealed a range of bioactive applications that have been studied, including their role as antioxidant [ 23 , 24 , 25 ], antiviral [ 26 , 27 , 28 , 29 ], antibacterial [ 30 ], antihyperlipidemic [ 31 ], anticoagulant [ 25 , 26 ], antitumor, and immunomodulatory agents [ 32 , 33 , 34 ], enabling them to be used in the biomedical field as potential pharmaceutical formulations for the treatment of various diseases.…”