A hydrogel comprising a fibrous network of a plurality of peptides and at least one biocompatible polymer, wherein each of said peptides is an aromatic homodipeptide composed of two aromatic amino acid residues that are identical with respect to their side-chain residue, said peptides being capable of self-assembling in an aqueous solution so as to form a hydrogel, and said biocompatible polymer is a polysaccharide featuring at least one characteristic selected from the group consisting of: (i) a storage modulus G' lower than 500 Pa at 10 Hz frequency and at 25 °C; (ii) a swelling ratio higher than 500; (iii) a viscosity at 0.1 Sec -1 shear rate and at 25 °C, lower than 300 Pa·s; and (iv) a viscosity recovery after shear of at least 95 %, the hydrogel being a hybrid hydrogel; is being devoid of a chemical cross-linking agent; and is being characterized by at least one of: a shear storage modulus (G') that is lower by at least 10 % of the storage modulus (G') of a hydrogel formed of said plurality of peptides in an aqueous solution; a storage modulus G' that is higher by at least 5-folds of a storage modulus G' of an aqueous solution of said biocompatible polymer; a viscosity higher by at least 10 % of a viscosity of said biocompatible polymer; a viscosity change through time higher by at least 2-folds than a viscosity change through time of said biocompatible polymer; viscosity recovery after shear that is at least 2-folds higher than that of a hydrogel formed of said plurality of peptides in an aqueous solution; a swelling ratio higher by at least 5 % of a swelling ratio of a hydrogel formed of said plurality of peptides in an aqueous solution; biocompatibility to cell viability higher by at least 2-folds than a biocompatibility to cell viability of a hydrogel formed of said plurality of peptides in an aqueous solution; and a biodegradation rate that is lower by at least 2-folds than the biodegradation rate of said biocompatible polymer. (i) a storage modulus G' lower than 500 Pa at 10 Hz frequency and at 25 °C; (ii) a swelling ratio higher than 500; (iii) a viscosity at 0.1 Sec -1 shear rate and at 25 °C, lower than 300 Pa·s; and (iv) a viscosity recovery after shear of at least 95 %, a shear storage modulus (G') that is lower by at least 10 % of the storage modulus (G') of a hydrogel formed of said plurality of peptides in an aqueous solution; a storage modulus G' that is higher by at least 5-folds of a storage modulus G' of an aqueous solution of said biocompatible polymer; a viscosity higher by at least 10 % of a viscosity of said biocompatible polymer; a viscosity change through time higher by at least 2-folds than a viscosity change through time of said biocompatible polymer; viscosity recovery after shear that is at least 2-folds higher than that of a hydrogel formed of said plurality of peptides in an aqueous solution; a swelling ratio higher by at least 5 % of a swelling ratio of a hydrogel formed of said plurality of peptides in an aqueous solution; biocompatibility to cell viability higher by at least 2-folds than a biocompatibility to cell viability of a hydrogel formed of said plurality of peptides in an aqueous solution; and a biodegradation rate that is lower by at least 2-folds than the biodegradation rate of said biocompatible polymer.